sh: userimask.c needs linux/stat.h

This fix the problem that S_IRUSR and S_IWUSR are not solved in userimask.c.

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CC drivers/usb/host/r8a66597-hcd.o
drivers/sh/intc/userimask.c:57: error: ‘S_IRUSR’ undeclared here (not in a function)
drivers/sh/intc/userimask.c:57: error: ‘S_IWUSR’ undeclared here (not in a function)
CC drivers/watchdog/shwdt.o
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Signed-off-by: Nobuhiro Iwamatsu <[e-mail]>
Signed-off-by: Paul Mundt <[e-mail]>

drivers/sh/intc/userimask.c

···
 #include <linux/sysdev.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/stat.h>
 #include <asm/sizes.h>
 #include "internals.h"