sunxi: Enable CMD_GPT by default

GPT is pretty common these days and can be useful for things like fastboot.
Add a platform imply, so that users can still opt out if they wish so.

Reviewed-by: Jagan Teki <jagan@openedev.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index f4256ec..7957115 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -694,6 +694,7 @@
 	select USB_STORAGE if DISTRO_DEFAULTS
 	select USB_KEYBOARD if DISTRO_DEFAULTS
 	select USE_TINY_PRINTF
+	imply CMD_GPT
 	imply FAT_WRITE
 	imply PRE_CONSOLE_BUFFER
 	imply SPL_GPIO_SUPPORT