avr32/lib: fix unaligned memcpy where len < 4

in case of memcpy(p, unaligned, 1..3) we get 1..3 as the
return value instead of p
Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>

arch/avr32/lib/memcpy.S

@@ -49,6 +49,7 @@ memcpy:
 
 	/* Handle unaligned "from" pointer */
 1:	sub	r10, 4
+	movlt	r9, r12
 	brlt	4b
 	add	r10, r9
 	lsl	r9, 2