sh: Add support pin function control using GPIO

Renesas SH and R-Mobile set up device using PFC.
This provide the framework. Most codes were brought from linux kernel.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 32a2474..106549d 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -40,6 +40,7 @@
 COBJS-$(CONFIG_DA8XX_GPIO)	+= da8xx_gpio.o
 COBJS-$(CONFIG_ALTERA_PIO)	+= altera_pio.o
 COBJS-$(CONFIG_MPC83XX_GPIO)	+= mpc83xx_gpio.o
+COBJS-$(CONFIG_SH_GPIO_PFC)	+= sh_pfc.o
 
 COBJS	:= $(COBJS-y)
 SRCS 	:= $(COBJS:.o=.c)