imx: mx6ull_14x14_evk: add plugin defconfig

Add defconfig file to use plugin code.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>

configs/mx6ull_14x14_evk_plugin_defconfig

+CONFIG_ARM=y
+CONFIG_ARCH_MX6=y
+CONFIG_TARGET_MX6ULL_14X14_EVK=y
+CONFIG_USE_IMXIMG_PLUGIN=y
+CONFIG_DEFAULT_DEVICE_TREE="imx6ull-14x14-evk"
+CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=board/freescale/mx6ullevk/imximage.cfg"
+CONFIG_BOOTDELAY=3
+CONFIG_HUSH_PARSER=y
+CONFIG_CMD_BOOTZ=y
+# CONFIG_CMD_IMLS is not set
+CONFIG_CMD_MEMTEST=y
+CONFIG_CMD_MMC=y
+CONFIG_CMD_I2C=y
+CONFIG_CMD_GPIO=y
+CONFIG_CMD_DHCP=y
+CONFIG_CMD_PING=y
+CONFIG_CMD_CACHE=y
+CONFIG_CMD_EXT2=y
+CONFIG_CMD_EXT4=y
+CONFIG_CMD_EXT4_WRITE=y
+CONFIG_CMD_FAT=y
+CONFIG_CMD_FS_GENERIC=y
+CONFIG_OF_CONTROL=y
+CONFIG_DM_GPIO=y
+CONFIG_DM_74X164=y
+CONFIG_DM_I2C=y
+CONFIG_DM_MMC=y
+# CONFIG_BLK is not set
+# CONFIG_DM_MMC_OPS is not set
+CONFIG_PINCTRL=y
+CONFIG_PINCTRL_IMX6=y
+CONFIG_DM_REGULATOR=y
+CONFIG_DM_SPI=y