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/r7-tv-dongle_defconfig b/configs/r7-tv-dongle_defconfig
index 35b66f0..1185d5d 100644
--- a/configs/r7-tv-dongle_defconfig
+++ b/configs/r7-tv-dongle_defconfig
@@ -1,5 +1,5 @@
 CONFIG_SPL=y
-CONFIG_SYS_EXTRA_OPTIONS="R7DONGLE,SPL,AXP152_POWER,USB_EHCI,SUNXI_USB_VBUS0_GPIO=SUNXI_GPG(13)"
+CONFIG_SYS_EXTRA_OPTIONS="R7DONGLE,AXP152_POWER,USB_EHCI,SUNXI_USB_VBUS0_GPIO=SUNXI_GPG(13)"
 CONFIG_FTDFILE="sun5i-a10s-r7-tv-dongle.dtb"
 +S:CONFIG_ARM=y
 +S:CONFIG_TARGET_SUN5I=y