sunxi: Convert CONFIG_SATAPWR to Kconfig

Convert the CONFIG_SATAPWR into kconfig.
Thanks to that, many SYS_EXTRA_OPTIONS can be removed from some
defconfigs.

Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
diff --git a/configs/Itead_Ibox_A20_defconfig b/configs/Itead_Ibox_A20_defconfig
index bba0c59..4bae19f 100644
--- a/configs/Itead_Ibox_A20_defconfig
+++ b/configs/Itead_Ibox_A20_defconfig
@@ -3,10 +3,10 @@
 CONFIG_MACH_SUN7I=y
 CONFIG_DRAM_CLK=480
 CONFIG_MMC0_CD_PIN="PH1"
+CONFIG_SATAPWR="PB8"
 CONFIG_DEFAULT_DEVICE_TREE="sun7i-a20-itead-ibox"
 CONFIG_AHCI=y
 # CONFIG_SYS_MALLOC_CLEAR_ON_INIT is not set
-CONFIG_SYS_EXTRA_OPTIONS="SATAPWR=SUNXI_GPB(8)"
 CONFIG_SPL=y
 CONFIG_SPL_I2C_SUPPORT=y
 # CONFIG_CMD_IMLS is not set