[ARM] Remove RETINSTR macro

RETINSTR is a left-over from the days when we had 26-bit and
32-bit CPU support integrated into the same tree.  Since this
is no longer the case, we can now remove RETINSTR.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/lib/strchr.S b/arch/arm/lib/strchr.S
index 5b9b493..9f18d6f 100644
--- a/arch/arm/lib/strchr.S
+++ b/arch/arm/lib/strchr.S
@@ -23,4 +23,4 @@
 		teq	r2, r1
 		movne	r0, #0
 		subeq	r0, r0, #1
-		RETINSTR(mov,pc,lr)
+		mov	pc, lr