m32r: fix __get_user()

commit c90a3bc5 upstream.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

arch/m32r/include/asm/uaccess.h

@@ -215,7 +215,7 @@ extern int fixup_exception(struct pt_regs *regs);
 #define __get_user_nocheck(x,ptr,size)					\
 ({									\
 	long __gu_err = 0;						\
-	unsigned long __gu_val;						\
+	unsigned long __gu_val = 0;					\
 	might_fault();							\
 	__get_user_size(__gu_val,(ptr),(size),__gu_err);		\
 	(x) = (__typeof__(*(ptr)))__gu_val;				\