Add own mkimage back #68

Job	Run time
build (rock-5b, Debug)	4m 23s
build (rock-5b, Release)	4m 29s
build (rock-5a, Debug)	5m 38s
build (rock-5a, Release)	4m 36s
build (orangepi-5, Debug)	4m 22s
build (orangepi-5, Release)	4m 45s
build (orangepi-5plus, Debug)	4m 16s
build (orangepi-5plus, Release)	4m 18s
build (indiedroid-nova, Debug)	4m 16s
build (indiedroid-nova, Release)	4m 40s
build (roc-rk3588s-pc, Debug)	5m 20s
build (roc-rk3588s-pc, Release)	4m 30s
build (station-m3, Debug)	4m 28s
build (station-m3, Release)	5m 30s
build (r58x, Debug)	5m 56s
build (r58x, Release)	4m 39s
build (r58-mini, Debug)	4m 29s
build (r58-mini, Release)	5m 44s
build (edge2, Debug)	5m 58s
build (edge2, Release)	5m 25s
build (nanopc-t6, Debug)	5m 59s
build (nanopc-t6, Release)	5m 19s
	1h 49m 0s

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