ARM: shmobile: r8a7778: Register PFC device

Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
diff --git a/arch/arm/mach-shmobile/Kconfig b/arch/arm/mach-shmobile/Kconfig
index 1a517e2..06da4d3 100644
--- a/arch/arm/mach-shmobile/Kconfig
+++ b/arch/arm/mach-shmobile/Kconfig
@@ -37,6 +37,7 @@
 
 config ARCH_R8A7778
 	bool "R-Car M1 (R8A77780)"
+	select ARCH_WANT_OPTIONAL_GPIOLIB
 	select CPU_V7
 	select SH_CLK_CPG
 	select ARM_GIC