ARM: imx_v6_v7_defconfig: Add GPIO_PCF857X

The imx6q-logicpd board has a PCF8575 connected to it, so this
patch turns it on my default now.
Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/configs/imx_v6_v7_defconfig

@@ -214,6 +214,7 @@ CONFIG_GPIO_SYSFS=y
 CONFIG_GPIO_MAX732X=y
 CONFIG_GPIO_MC9S08DZ60=y
 CONFIG_GPIO_PCA953X=y
+CONFIG_GPIO_PCF857X=y
 CONFIG_GPIO_STMPE=y
 CONFIG_GPIO_74X164=y
 CONFIG_POWER_RESET=y