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/corvus_defconfig b/configs/corvus_defconfig
index 9210493..42c0a48 100644
--- a/configs/corvus_defconfig
+++ b/configs/corvus_defconfig
@@ -5,7 +5,7 @@
 CONFIG_ARCH_AT91=y
 CONFIG_SYS_TEXT_BASE=0x72000000
 CONFIG_TARGET_CORVUS=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=0x800