ARM: 6653/1: bitops: Use BX instead of MOV PC,LR

The kernel doesn't officially need to interwork, but using BX
wherever appropriate will help educate people into good assembler
coding habits.

BX is appropriate here because this code is predicated on
__LINUX_ARM_ARCH__ >= 6

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/lib/bitops.h

@@ -12,7 +12,7 @@
 	strex	r0, r2, [r1]
 	cmp	r0, #0
 	bne	1b
-	mov	pc, lr
+	bx	lr
 	.endm
 
 	.macro	testop, instr, store
@@ -33,7 +33,7 @@
 	smp_dmb
 	cmp	r0, #0
 	movne	r0, #1
-2:	mov	pc, lr
+2:	bx	lr
 	.endm
 #else
 	.macro	bitop, instr