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/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
index eff4899..cd69664 100644
--- a/arch/arm/mach-omap2/Kconfig
+++ b/arch/arm/mach-omap2/Kconfig
@@ -15,7 +15,7 @@
 	imply NAND_OMAP_GPMC
 	imply SPL_FS_EXT4
 	imply SPL_FS_FAT
-	imply SPL_GPIO_SUPPORT
+	imply SPL_GPIO
 	imply SPL_I2C_SUPPORT
 	imply SPL_LIBCOMMON_SUPPORT
 	imply SPL_LIBDISK_SUPPORT
@@ -37,7 +37,7 @@
 	imply SPL_DISPLAY_PRINT
 	imply SPL_FS_EXT4
 	imply SPL_FS_FAT
-	imply SPL_GPIO_SUPPORT
+	imply SPL_GPIO
 	imply SPL_I2C_SUPPORT
 	imply SPL_LIBCOMMON_SUPPORT
 	imply SPL_LIBDISK_SUPPORT
@@ -61,7 +61,7 @@
 	imply SPL_ENV_SUPPORT
 	imply SPL_FS_EXT4
 	imply SPL_FS_FAT
-	imply SPL_GPIO_SUPPORT
+	imply SPL_GPIO
 	imply SPL_I2C_SUPPORT
 	imply SPL_LIBCOMMON_SUPPORT
 	imply SPL_LIBDISK_SUPPORT