SH: annotate code after BUG() as unreachable

This squashes some warnings:

CC mm/bootmem.o
mm/bootmem.c: In function 'mark_bootmem':
mm/bootmem.c:379:1: warning: control reaches end of non-void function [-Wreturn-type]

CC kernel/sched/core.o
kernel/sched/core.c: In function 'pick_next_task':
kernel/sched/core.c:2610:1: warning: control reaches end of non-void function [-Wreturn-type]

---
 arch/sh/include/asm/bug.h | 1 +
 1 file changed, 1 insertion(+)

index dcf278075429..1ae948f309f2 100644
@@ -48,6 +48,7 @@ do {							\
 		   "i" (__FILE__),			\
 		   "i" (__LINE__), "i" (0),		\
 		   "i" (sizeof(struct bug_entry)));	\
+	unreachable();					\
 } while (0)
 
 #define __WARN_TAINT(taint)				\

1.9.1