[Backport stable] image: add ffbs-collect-debug-info #679

Job	Run time
generate_target_matrix	3s
build_firmware (ath79-generic)	1h 17m 39s
build_firmware (ath79-mikrotik)	1h 10m 42s
build_firmware (ath79-nand)	1h 12m 19s
build_firmware (bcm27xx-bcm2708)	1h 6m 9s
build_firmware (bcm27xx-bcm2709)	1h 12m 27s
build_firmware (bcm27xx-bcm2710)	1h 19m 5s
build_firmware (bcm27xx-bcm2711)	1h 18m 59s
build_firmware (ipq40xx-generic)	1h 14m 10s
build_firmware (ipq40xx-mikrotik)	1h 11m 35s
build_firmware (ipq806x-generic)	1h 13m 14s
build_firmware (lantiq-xrx200)	1h 16m 29s
build_firmware (lantiq-xway)	1h 12m 4s
build_firmware (mediatek-mt7622)	1h 19m 3s
build_firmware (mpc85xx-p1010)	1h 10m 32s
build_firmware (mpc85xx-p1020)	1h 11m 33s
build_firmware (mvebu-cortexa9)	1h 11m 0s
build_firmware (ramips-mt7620)	1h 12m 49s
build_firmware (ramips-mt7621)	1h 16m 41s
build_firmware (ramips-mt76x8)	1h 12m 8s
build_firmware (realtek-rtl838x)	1h 1m 13s
build_firmware (rockchip-armv8)	1h 19m 33s
build_firmware (sunxi-cortexa7)	1h 6m 39s
build_firmware (x86-64)	1h 25m 27s
build_firmware (x86-generic)	1h 20m 35s
build_firmware (x86-geode)	1h 15m 43s
build_firmware (x86-legacy)	1h 17m 9s
create_release	0s
	1d 8h 5m 0s

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