armv8/ls1043ardb: add DSPI support

Use the U-Boot Driver Model. Just enable Freescale DSPI driver
and set DSPI related parameters in dts file.

Signed-off-by: Gong Qianyu <Qianyu.Gong@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/configs/ls1043ardb_defconfig b/configs/ls1043ardb_defconfig
index 64c1c86..8622ce7 100644
--- a/configs/ls1043ardb_defconfig
+++ b/configs/ls1043ardb_defconfig
@@ -4,3 +4,6 @@
 CONFIG_SYS_NS16550=y
 CONFIG_DEFAULT_DEVICE_TREE="fsl-ls1043a-rdb"
 CONFIG_OF_CONTROL=y
+CONFIG_DM=y
+CONFIG_SPI_FLASH=y
+CONFIG_DM_SPI=y