ARM: imx_v6_v7_defconfig: enable imx6sll by default

enable i.mx6sll support by default in defconfig.
Signed-off-by: NBai Ping <ping.bai@nxp.com>
Signed-off-by: NShawn Guo <shawnguo@kernel.org>

arch/arm/configs/imx_v6_v7_defconfig

@@ -38,6 +38,7 @@ CONFIG_SOC_IMX51=y
 CONFIG_SOC_IMX53=y
 CONFIG_SOC_IMX6Q=y
 CONFIG_SOC_IMX6SL=y
+CONFIG_SOC_IMX6SLL=y
 CONFIG_SOC_IMX6SX=y
 CONFIG_SOC_IMX6UL=y
 CONFIG_SOC_IMX7D=y