xen/sched: address violations of MISRA C:2012 Directive 4.10

Add inclusion guards to address violations of
MISRA C:2012 Directive 4.10 ("Precautions shall be taken in order
to prevent the contents of a header file being included more than
once").

Mechanical change.

Signed-off-by: Simone Ballarin <simone.ballarin@bugseng.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: George Dunlap <george.dunlap@cloud.com>

xen/common/sched/compat.c

@@ -3,6 +3,10 @@
  *
  */
 
+#ifndef __COMMON_SCHED_COMPAT_C__
+#define __COMMON_SCHED_COMPAT_C__
+
+
 #include <compat/sched.h>
 
 #define COMPAT
@@ -44,6 +48,8 @@ int compat_set_timer_op(uint32_t lo, int32_t hi)
     return do_set_timer_op(((s64)hi << 32) | lo);
 }
 
+#endif /* __COMMON_SCHED_COMPAT_C__ */
+
 /*
  * Local variables:
  * mode: C