[MIPS] Remove a duplicated local variable in test_and_clear_bit()

Fix a sparse warning caused by 2c921d07f8c641e691b0dfd80a5cfe14c60ec489

include2/asm/bitops.h:313:23: warning: symbol 'res' shadows an earlier one
include2/asm/bitops.h:309:16: originally declared here
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

include/asm-mips/bitops.h

@@ -310,7 +310,7 @@ static inline int test_and_clear_bit(unsigned long nr,
 
 	if (cpu_has_llsc && R10000_LLSC_WAR) {
 		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
-		unsigned long temp, res;
+		unsigned long temp;
 
 		__asm__ __volatile__(
 		"	.set	mips3					\n"