linux: Fix integer overflow warnings when including <sys/mount.h> [BZ #32708]

Using gcc -Wshift-overflow=2 -Wsystem-headers to compile a file
including <sys/mount.h> will cause a warning since 1 << 31 is undefined
behavior on platforms where int is 32-bits.

Signed-off-by: Collin Funk <[email protected]>
Tested-by: Carlos O'Donell <[email protected]>
Reviewed-by: Carlos O'Donell <[email protected]>

Author: collinfunk

sysdeps/unix/sysv/linux/sys/mount.h

@@ -121,7 +121,7 @@ enum
   MS_ACTIVE = 1 << 30,
 #define MS_ACTIVE	MS_ACTIVE
 #undef MS_NOUSER
-  MS_NOUSER = 1 << 31
+  MS_NOUSER = 1U << 31
 #define MS_NOUSER	MS_NOUSER
 };