board/freescale: imx9-bootloader-prepare.sh: fix script

Commit c05f27c "configs/freescale_imx93evk: new defconfig", when
applied, added few ShellCheck fixups on top of the orginial
submission. During those changes, one extra backslash was added,
making the imx9-bootloader-prepare.sh fail.

This commit fixes the issue by removing this extra backslash.

Fixes:

    dd: failed to open '/buildroot/output/images/u-boot-atf-container.img': No such file or directory
    make: *** [Makefile:820: target-post-image] Error 1

Signed-off-by: Julien Olivain <ju.o@free.fr>
Reviewed-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com>
Tested-By: Sébastien Szymanski <sebastien.szymanski@armadeus.com>
Signed-off-by: Arnout Vandecappelle <arnout@mind.be>

board/freescale/common/imx/imx9-bootloader-prepare.sh

@@ -21,7 +21,7 @@ main ()
 			-ap "${BINARIES_DIR}/bl31.bin" a35 ${ATF_LOAD_ADDR} \
 			-ap "${BINARIES_DIR}/u-boot-hash.bin" a35 0x80200000 \
 			-ap "${BINARIES_DIR}/tee.bin" a35 0x96000000 \
-			-out "${BINARIES_DIR}/u-boot-atf-container.img" \
+			-out "${BINARIES_DIR}/u-boot-atf-container.img"
 	else
 		"${HOST_DIR}/bin/mkimage_imx8" -soc IMX9 -c \
 			-ap "${BINARIES_DIR}/bl31.bin" a35 ${ATF_LOAD_ADDR} \