sh: rts7751r2d board updates.

This tidies up some of the rts7751r2d mess and gets it booting
again. Update the defconfig, too.

Signed-off-by: Masayuki Hosokawa <hosokawa@ace-jp.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/boards/renesas/rts7751r2d/Makefile b/arch/sh/boards/renesas/rts7751r2d/Makefile
index 833de1e..0d4c75a 100644
--- a/arch/sh/boards/renesas/rts7751r2d/Makefile
+++ b/arch/sh/boards/renesas/rts7751r2d/Makefile
@@ -2,4 +2,4 @@
 # Makefile for the RTS7751R2D specific parts of the kernel
 #
 
-obj-y	 := setup.o io.o irq.o
+obj-y	 := setup.o irq.o