sh: Fix up psw build rules for r7780rp.

When reordering the Makefile rules, the psw support was being
clobbered. Fix it up so it's linked in again.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/boards/renesas/r7780rp/Makefile

@@ -3,5 +3,5 @@
 #
 irqinit-y			:= irq-r7780rp.o
 irqinit-$(CONFIG_SH_R7785RP)	:= irq-r7785rp.o
-obj-$(CONFIG_PUSH_SWITCH)	+= psw.o
 obj-y	 			:= setup.o irq.o $(irqinit-y)
+obj-$(CONFIG_PUSH_SWITCH)	+= psw.o