arm64: defconfig: Enable QorIQ GPIO driver

Enables generic GPIO driver for varous QorIQ SoCs.  The driver can only
be built-in right now.
Signed-off-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/configs/defconfig

@@ -441,6 +441,7 @@ CONFIG_PINCTRL_SM8150=y
 CONFIG_GPIO_ALTERA=m
 CONFIG_GPIO_DWAPB=y
 CONFIG_GPIO_MB86S7X=y
+CONFIG_GPIO_MPC8XXX=y
 CONFIG_GPIO_PL061=y
 CONFIG_GPIO_RCAR=y
 CONFIG_GPIO_UNIPHIER=y