[ARM] versatile: add PL061 gpiolib support

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index aef63c8..e4971e4 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -229,6 +229,7 @@
 	select ICST307
 	select GENERIC_TIME
 	select GENERIC_CLOCKEVENTS
+	select ARCH_WANT_OPTIONAL_GPIOLIB
 	help
 	  This enables support for ARM Ltd Versatile board.