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/am335x_shc_ict_defconfig b/configs/am335x_shc_ict_defconfig
index 4ec255f..ca6e865 100644
--- a/configs/am335x_shc_ict_defconfig
+++ b/configs/am335x_shc_ict_defconfig
@@ -1,7 +1,7 @@
 CONFIG_ARM=y
 CONFIG_ARCH_CPU_INIT=y
 CONFIG_ARCH_OMAP2PLUS=y
-CONFIG_SPL_GPIO_SUPPORT=y
+CONFIG_SPL_GPIO=y
 CONFIG_SPL_LIBCOMMON_SUPPORT=y
 CONFIG_SPL_LIBGENERIC_SUPPORT=y
 CONFIG_ENV_SIZE=0x1000