kconfig: remove redundant "SPL" from CONFIG_SYS_EXTRA_OPTIONS

CONFIG_SPL is defined as a primary option in Kconfig.
It should not be added to CONFIG_SYS_EXTRA_OPTIONS.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>
diff --git a/configs/Bananapi_defconfig b/configs/Bananapi_defconfig
index dc68469..2da2d36 100644
--- a/configs/Bananapi_defconfig
+++ b/configs/Bananapi_defconfig
@@ -1,5 +1,5 @@
 CONFIG_SPL=y
-CONFIG_SYS_EXTRA_OPTIONS="BANANAPI,SPL,AXP209_POWER,SUNXI_GMAC,RGMII,MACPWR=SUNXI_GPH(23),AHCI,USB_EHCI"
+CONFIG_SYS_EXTRA_OPTIONS="BANANAPI,AXP209_POWER,SUNXI_GMAC,RGMII,MACPWR=SUNXI_GPH(23),AHCI,USB_EHCI"
 CONFIG_FTDFILE="sun7i-a20-bananapi.dtb"
 +S:CONFIG_ARM=y
 +S:CONFIG_TARGET_SUN7I=y