configs/imx6q-sabresd_defconfig: Switch to SPL boot

U-Boot 2017.07 has switched to SPL boot, which allows the same binary to
boot on imx6dl, imx6q and imx6qp sabresd boards.

Switch to the SPL mechanism.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

configs/imx6q-sabresd_defconfig

@@ -22,10 +22,12 @@ BR2_TARGET_ROOTFS_EXT2_4=y
 
 # Bootloader
 BR2_TARGET_UBOOT=y
-BR2_TARGET_UBOOT_BOARDNAME="mx6qsabresd"
+BR2_TARGET_UBOOT_BOARDNAME="mx6sabresd"
 BR2_TARGET_UBOOT_CUSTOM_VERSION=y
-BR2_TARGET_UBOOT_CUSTOM_VERSION_VALUE="2017.05"
-BR2_TARGET_UBOOT_FORMAT_IMX=y
+BR2_TARGET_UBOOT_CUSTOM_VERSION_VALUE="2017.07"
+BR2_TARGET_UBOOT_FORMAT_IMG=y
+BR2_TARGET_UBOOT_SPL=y
+BR2_TARGET_UBOOT_SPL_NAME="SPL"
 
 # Kernel
 BR2_LINUX_KERNEL=y
@@ -33,4 +35,4 @@ BR2_LINUX_KERNEL_CUSTOM_VERSION=y
 BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="4.13"
 BR2_LINUX_KERNEL_DEFCONFIG="imx_v6_v7"
 BR2_LINUX_KERNEL_DTS_SUPPORT=y
-BR2_LINUX_KERNEL_INTREE_DTS_NAME="imx6q-sabresd"
+BR2_LINUX_KERNEL_INTREE_DTS_NAME="imx6q-sabresd imx6dl-sabresd imx6qp-sabresd"