os: unexport AccessUsingXdmcp()

This function is only used internally for xdmcp auth handling, not used
in modules/drivers, so no need to export it.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1344>

include/os.h

@@ -326,9 +326,6 @@ GetClientFd(ClientPtr);
 extern _X_EXPORT Bool
 ClientIsLocal(ClientPtr client);
 
-extern _X_EXPORT void
-AccessUsingXdmcp(void);
-
 extern _X_EXPORT int
 ddxProcessArgument(int /*argc */ , char * /*argv */ [], int /*i */ );
 

os/auth.h

@@ -109,4 +109,6 @@ void AugmentSelf(void *from, int len);
 
 int ChangeAccessControl(ClientPtr client, int fEnabled);
 
+void AccessUsingXdmcp(void);
+
 #endif /* _XSERVER_OS_AUTH_H */