MIPS: asm: futex: Set the appropriate ISA level for MIPS R6

MIPS R6 changed the opcodes for LL/SC instructions so we need to set
the appropriate ISA level.

Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>

arch/mips/include/asm/futex.h

@@ -53,11 +53,11 @@
 		__asm__ __volatile__(					\
 		"	.set	push				\n"	\
 		"	.set	noat				\n"	\
-		"	.set	arch=r4000			\n"	\
+		"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"	\
 		"1:	"user_ll("%1", "%4")" # __futex_atomic_op\n"	\
 		"	.set	mips0				\n"	\
 		"	" insn	"				\n"	\
-		"	.set	arch=r4000			\n"	\
+		"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"	\
 		"2:	"user_sc("$1", "%2")"			\n"	\
 		"	beqz	$1, 1b				\n"	\
 		__WEAK_LLSC_MB						\
@@ -183,12 +183,12 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
 		"# futex_atomic_cmpxchg_inatomic			\n"
 		"	.set	push					\n"
 		"	.set	noat					\n"
-		"	.set	arch=r4000				\n"
+		"	.set	"MIPS_ISA_ARCH_LEVEL"			\n"
 		"1:	"user_ll("%1", "%3")"				\n"
 		"	bne	%1, %z4, 3f				\n"
 		"	.set	mips0					\n"
 		"	move	$1, %z5					\n"
-		"	.set	arch=r4000				\n"
+		"	.set	"MIPS_ISA_ARCH_LEVEL"			\n"
 		"2:	"user_sc("$1", "%2")"				\n"
 		"	beqz	$1, 1b					\n"
 		__WEAK_LLSC_MB