imx: Fix imx8m FIT script issue

The FIT config node has reversed ATF and u-boot: ATF is set to 'firmware' but
u-boot is set to 'loadables'.
This script can work previously because spl fit driver wrongly appends fdt to
all loadable images. With the issue fixed in commit 9d15d1d1c24f ("Revert
"common: spl_fit: Default to IH_OS_U_BOOT if FIT_IMAGE_TINY enabled"") the
u-boot in 'loadables' does not have fdt appended and fails to work.  So correct
the script by moving u-boot to 'firmware' and ATF to 'loadables'.

Signed-off-by: Ye Li <ye.li@nxp.com>
Reported-by: Matt Porter <mporter@konsulko.com>
Tested-by: Matt Porter <mporter@konsulko.com>
diff --git a/arch/arm/mach-imx/mkimage_fit_atf.sh b/arch/arm/mach-imx/mkimage_fit_atf.sh
index ad81d5e..dd1ca5a 100755
--- a/arch/arm/mach-imx/mkimage_fit_atf.sh
+++ b/arch/arm/mach-imx/mkimage_fit_atf.sh
@@ -116,8 +116,8 @@
 cat << __CONF_SECTION_EOF
 		config@$cnt {
 			description = "$(basename $dtname .dtb)";
-			firmware = "atf@1";
-			loadables = "uboot@1", "tee@1";
+			firmware = "uboot@1";
+			loadables = "atf@1", "tee@1";
 			fdt = "fdt@$cnt";
 		};
 __CONF_SECTION_EOF
@@ -125,8 +125,8 @@
 cat << __CONF_SECTION1_EOF
 		config@$cnt {
 			description = "$(basename $dtname .dtb)";
-			firmware = "atf@1";
-			loadables = "uboot@1";
+			firmware = "uboot@1";
+			loadables = "atf@1";
 			fdt = "fdt@$cnt";
 		};
 __CONF_SECTION1_EOF