Rename GPIO_SUPPORT to GPIO

Rename these options so that CONFIG_IS_ENABLED can be used with them.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/sama5d27_giantboard_defconfig b/configs/sama5d27_giantboard_defconfig
index 34f259f..fe2b98b 100644
--- a/configs/sama5d27_giantboard_defconfig
+++ b/configs/sama5d27_giantboard_defconfig
@@ -3,7 +3,7 @@
 CONFIG_ARCH_AT91=y
 CONFIG_SYS_TEXT_BASE=0x23f00000
 CONFIG_TARGET_SAMA5D27_SOM1_EK=y
-CONFIG_SPL_GPIO_SUPPORT=y
+CONFIG_SPL_GPIO=y
 CONFIG_SPL_LIBCOMMON_SUPPORT=y
 CONFIG_SPL_LIBGENERIC_SUPPORT=y
 CONFIG_SYS_MALLOC_F_LEN=0x2000