sh: Fix up asm/hw_breakpoint.h header check.

Presently headers_check complains about linux/kdebug.h being unexported,
so just bump the __KERNEL__ ifdef up, as per the x86 change.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/include/asm/hw_breakpoint.h

 #ifndef __ASM_SH_HW_BREAKPOINT_H
 #define __ASM_SH_HW_BREAKPOINT_H
 
-#include <linux/kdebug.h>
-#include <linux/types.h>
-
 #ifdef __KERNEL__
 #define __ARCH_HW_BREAKPOINT_H
 
+#include <linux/kdebug.h>
+#include <linux/types.h>
+
 struct arch_hw_breakpoint {
 	char		*name; /* Contains name of the symbol to set bkpt */
 	unsigned long	address;