apalis_imx6: add update_uboot wrapper

Add universal update_uboot wrapper that helps to update
U-Boot image on internal storage.

Usage example:
> tftpboot ${loadaddr} ${board_name}/u-boot.img
> run update_uboot
> tftpboot ${loadaddr} ${board_name}/SPL
> run update_spl

Signed-off-by: Igor Opaniuk <igor.opaniuk@toradex.com>
diff --git a/include/configs/apalis_imx6.h b/include/configs/apalis_imx6.h
index 50a4391..800f27c 100644
--- a/include/configs/apalis_imx6.h
+++ b/include/configs/apalis_imx6.h
@@ -121,6 +121,17 @@
 	"imx6q-apalis-eval.dtb fat 0 1;" \
 	"imx6q-apalis-cam-eval.dtb fat 0 1"
 
+#define UBOOT_UPDATE \
+	"uboot_hwpart=1\0" \
+	"uboot_blk=8a\0" \
+	"uboot_spl_blk=2\0" \
+	"set_blkcnt=setexpr blkcnt ${filesize} + 0x1ff && " \
+		"setexpr blkcnt ${blkcnt} / 0x200\0" \
+	"update_uboot=run set_blkcnt && mmc dev 0 ${uboot_hwpart} && " \
+		"mmc write ${loadaddr} ${uboot_blk} ${blkcnt}\0" \
+	"update_spl=run set_blkcnt && mmc dev 0 ${uboot_hwpart} && " \
+		"mmc write ${loadaddr} ${uboot_spl_blk} ${blkcnt}\0"
+
 #define EMMC_BOOTCMD \
 	"set_emmcargs=setenv emmcargs ip=off root=PARTUUID=${uuid} " \
 		"ro,noatime rootfstype=ext4 rootwait\0" \
@@ -178,6 +189,7 @@
 	"fdt_fixup=;\0" \
 	MEM_LAYOUT_ENV_SETTINGS \
 	NFS_BOOTCMD \
+	UBOOT_UPDATE \
 	"setethupdate=if env exists ethaddr; then; else setenv ethaddr " \
 		"00:14:2d:00:00:00; fi; tftpboot ${loadaddr} " \
 		"flash_eth.img && source ${loadaddr}\0" \