Build: Use dri3proto/libdrm CFLAGS

Make sure we get the CFLAGS required for building DRI3 into the
command line.

Signed-off-by: Daniel Stone <daniels@collabora.com>

configure.ac

@@ -1197,6 +1197,7 @@ PKG_CHECK_MODULES([DRI3PROTO], $DRI3PROTO,
 
 case "$DRI3,$HAVE_DRI3PROTO" in
 	yes,yes | auto,yes)
+		REQUIRED_MODULES="$REQUIRED_MODULES dri3proto"
 		;;
 	yes,no)
 		AC_MSG_ERROR([DRI3 requested, but dri3proto not found.])

dri3/meson.build

@@ -9,7 +9,7 @@ if build_dri3
     libxserver_dri3 = static_library('libxserver_dri3',
         srcs_dri3,
         include_directories: inc,
-        dependencies: common_dep,
+        dependencies: [ common_dep, libdrm_dep ],
         c_args: '-DHAVE_XORG_CONFIG_H'
         )
 endif