Revert "Fix missing includes of <errno.h>"

Removing errno from xf86_OSlib.h breaks the xf86-input-mouse driver
build. And xf86_OSlib.h itself relies on errno anyway in the SYSCALL
macro provided by this header.

This reverts commit f6a367102c.

Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1423>

Xext/xselinux_hooks.c

@@ -26,7 +26,6 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <dix-config.h>
 #endif
 
-#include <errno.h>
 #include <sys/socket.h>
 #include <stdio.h>
 #include <stdarg.h>

hw/xfree86/common/xf86Configure.c

@@ -27,8 +27,6 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
-
 #include "xf86.h"
 #include "xf86Config.h"
 #include "xf86_OSlib.h"

hw/xfree86/common/xf86Events.c

@@ -53,11 +53,9 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
 #include <X11/X.h>
 #include <X11/Xproto.h>
 #include <X11/Xatom.h>
-
 #include "misc.h"
 #include "xf86.h"
 #include "xf86Priv.h"

hw/xfree86/drivers/modesetting/dri2.c

@@ -36,9 +36,7 @@
 #include "dix-config.h"
 #endif
 
-#include <errno.h>
 #include <time.h>
-
 #include "list.h"
 #include "xf86.h"
 #include "driver.h"

hw/xfree86/drivers/modesetting/driver.c

@@ -36,10 +36,8 @@
 #include "dix-config.h"
 #endif
 
-#include <errno.h>
 #include <unistd.h>
 #include <fcntl.h>
-
 #include "xf86.h"
 #include "xf86Priv.h"
 #include "xf86_OSproc.h"

hw/xfree86/drivers/modesetting/pageflip.c

@@ -24,8 +24,6 @@
 #include "dix-config.h"
 #endif
 
-#include <errno.h>
-
 #include <xserver_poll.h>
 #include <xf86drm.h>
 

hw/xfree86/drivers/modesetting/vblank.c

@@ -29,9 +29,7 @@
 #include "dix-config.h"
 #endif
 
-#include <errno.h>
 #include <unistd.h>
-
 #include <xf86.h>
 #include <xf86Crtc.h>
 #include "driver.h"

hw/xfree86/int10/generic.c

@@ -7,7 +7,6 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
 #include <string.h>
 #include <unistd.h>
 

hw/xfree86/os-support/bsd/alpha_video.c

@@ -27,9 +27,7 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
 #include <X11/X.h>
-
 #include "xf86.h"
 #include "xf86Priv.h"
 

hw/xfree86/os-support/bsd/arm_video.c

@@ -60,9 +60,7 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
 #include <X11/X.h>
-
 #include "xf86.h"
 #include "xf86Priv.h"
 #include "xf86_OSlib.h"

hw/xfree86/os-support/hurd/hurd_video.c

@@ -29,9 +29,8 @@
 #include <device/device.h>
 #include <mach/machine/mach_i386.h>
 #include <hurd.h>
-#include <errno.h>
-#include <X11/X.h>
 
+#include <X11/X.h>
 #include "input.h"
 #include "scrnintstr.h"
 

hw/xfree86/os-support/linux/lnx_agp.c

@@ -11,9 +11,7 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
 #include <X11/X.h>
-
 #include "xf86.h"
 #include "xf86Priv.h"
 #include "xf86_OSlib.h"

hw/xfree86/os-support/linux/lnx_init.c

@@ -27,7 +27,6 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
 #include <X11/X.h>
 #include <X11/Xmd.h>
 

hw/xfree86/os-support/shared/posix_tty.c

@@ -56,9 +56,7 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
 #include <X11/X.h>
-
 #include <xserver_poll.h>
 #include "xf86.h"
 #include "xf86Priv.h"

hw/xfree86/os-support/shared/sigio.c

@@ -56,9 +56,7 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
 #include <X11/X.h>
-
 #include <xserver_poll.h>
 #include "xf86.h"
 #include "xf86Priv.h"

hw/xfree86/os-support/solaris/sun_agp.c

@@ -32,9 +32,7 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
 #include <X11/X.h>
-
 #include "xf86.h"
 #include "xf86Priv.h"
 #include "xf86_OSlib.h"

hw/xfree86/os-support/solaris/sun_apm.c

@@ -53,9 +53,7 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
 #include <X11/X.h>
-
 #include "os.h"
 #include "xf86.h"
 #include "xf86Priv.h"

hw/xfree86/os-support/solaris/sun_bell.c

@@ -24,7 +24,6 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
 #include <sys/audio.h>
 #include <sys/uio.h>
 #include <limits.h>

hw/xfree86/os-support/solaris/sun_init.c

@@ -26,8 +26,6 @@
 #include <xorg-config.h>
 #endif
 
-#include <errno.h>
-
 #include "xf86.h"
 #include "xf86Priv.h"
 #include "xf86_OSlib.h"

hw/xfree86/os-support/xf86_OSlib.h

@@ -91,6 +91,8 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 
+#include <errno.h>
+
 #if defined(_NEED_SYSI86)
 #if !(defined (__sun) && defined (SVR4))
 #include <sys/immu.h>
@@ -186,6 +188,8 @@ extern _X_HIDDEN char xf86SolarisFbDev[PATH_MAX];
 #include <sys/param.h>
 #endif
 
+#include <errno.h>
+
 #include <sys/stat.h>
 
 #include <sys/mman.h>
@@ -215,6 +219,8 @@ extern _X_HIDDEN char xf86SolarisFbDev[PATH_MAX];
 #define termio termios
 #define POSIX_TTY
 
+#include <errno.h>
+
 #include <sys/types.h>
 #include <sys/mman.h>
 #include <sys/stat.h>

hw/xquartz/applewm.c

@@ -34,8 +34,6 @@
 #include <dix-config.h>
 #endif
 
-#include <errno.h>
-
 #include "quartz.h"
 
 #include "misc.h"

hw/xquartz/mach-startup/bundle-main.c

@@ -34,7 +34,6 @@
 #include <dix-config.h>
 #endif
 
-#include <errno.h>
 #include <X11/Xlib.h>
 #include <assert.h>
 #include <unistd.h>

hw/xwayland/xwayland-xtest.c

@@ -29,7 +29,6 @@
 #include <inpututils.h>
 #include <libgen.h>
 #include <unistd.h>
-#include <errno.h>
 
 #include <libei.h>
 

os/xdmcp.c

@@ -34,7 +34,6 @@
 #include <netdb.h>
 #endif
 
-#include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <X11/X.h>