imx: mx6sxsabreauto: Add support for mx6sx SABREAUTO board

Initial version for mx6sx SABREAUTO board support with features:
PMIC, QSPI, NAND flash, SD/MMC, USB, Ethernet, I2C, IO Expander.

Signed-off-by: Ye Li <ye.li@nxp.com>
diff --git a/configs/mx6sxsabreauto_defconfig b/configs/mx6sxsabreauto_defconfig
new file mode 100644
index 0000000..d9e35df
--- /dev/null
+++ b/configs/mx6sxsabreauto_defconfig
@@ -0,0 +1,11 @@
+CONFIG_ARM=y
+CONFIG_ARCH_MX6=y
+CONFIG_TARGET_MX6SXSABREAUTO=y
+CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=board/freescale/mx6sxsabreauto/imximage.cfg,MX6SX"
+# CONFIG_CMD_IMLS is not set
+# CONFIG_CMD_FLASH is not set
+CONFIG_CMD_GPIO=y
+# CONFIG_CMD_SETEXPR is not set
+CONFIG_SPI_FLASH=y
+CONFIG_SPI_FLASH_BAR=y
+CONFIG_SPI_FLASH_STMICRO=y