SAMSUNG: make s5p common gpio functions

Because of s5pc1xx gpio is same as s5p seires SoC,
move gpio functions to drvier/gpio/
and modify structure's name from s5pc1xx_ to s5p_.

Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index d966082..528ca2e 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -29,6 +29,7 @@
 COBJS-$(CONFIG_KIRKWOOD_GPIO)	+= kw_gpio.o
 COBJS-$(CONFIG_MX31_GPIO)	+= mx31_gpio.o
 COBJS-$(CONFIG_PCA953X)		+= pca953x.o
+COBJS-$(CONFIG_S5PC1XX)		+= s5p_gpio.o
 
 COBJS	:= $(COBJS-y)
 SRCS 	:= $(COBJS:.o=.c)