boot.cmd: clean up the variable on "for" loop

In some situation "for" loop don't alterate the non-empty iteration
variable [1]. Clean up the iteration var at the end of each loop.

[1]
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Apalis iMX6 # load ${devtype} ${devnum}:${distro_bootpart} ${loadaddr} ${overlays_file}; env import -t ${loadaddr} ${filesize}
107 bytes read in 11 ms (8.8 KiB/s)
Apalis iMX6 # print fdt_overlays
fdt_overlays="devicetree/apalis-imx6_parallel-rgb_overlay.dtbo devicetree/apalis-imx6_ov5640_overlay.dtbo"

Apalis iMX6 # for overlay_file in ${fdt_overlays}; do echo "file=${overlay_file}"; done
file=devicetree/apalis-imx6_parallel-rgb_overlay.dtbo
file=devicetree/apalis-imx6_parallel-rgb_overlay.dtbo

{Add clean up}
Apalis iMX6 # for overlay_file in ${fdt_overlays}; do echo "file=${overlay_file}"; setenv overlay_file; done
file=devicetree/apalis-imx6_parallel-rgb_overlay.dtbo
file=devicetree/apalis-imx6_ov5640_overlay.dtbo"
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Related-to: ELB-2797
Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>

0 files changed, 0 insertions, 0 deletions