ARM: S3C64XX: Ensure samsung_keypad_cfg_gpio() is prototyped

Since it's exported we should make sure we're using the prototype
others see.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

arch/arm/mach-s3c64xx/setup-keypad.c

@@ -12,6 +12,7 @@
 
 #include <linux/gpio.h>
 #include <plat/gpio-cfg.h>
+#include <plat/keypad.h>
 
 void samsung_keypad_cfg_gpio(unsigned int rows, unsigned int cols)
 {