rimage: elf_file: Fix elf_free behavior on unopened elf file #15705

Job	Run time
build-windows (imx8 imx8x imx8m)	6m 53s
build-linux (mnfst, imx8 imx8x imx8m)	4m 9s
build-windows (mtl)	6m 33s
LP64-WIP	3m 26s
build-linux (mnfst, mtl)	4m 4s
build-windows (tgl tgl-h)	7m 33s
build-linux (mnfst, lnl)	3m 57s
build-windows (-d, mtl)	5m 55s
manifest-check	42s
build-linux (mnfst, tgl tgl-h)	5m 23s
build-linux (zmain, imx8 imx8x imx8m)	3m 57s
build-linux (zmain, mtl)	3m 53s
build-linux (zmain, lnl)	4m 0s
build-linux (zmain, tgl tgl-h)	4m 46s
build-linux (-d, mnfst, mtl)	4m 20s
compare-linux-win	43s
	1h 10m 14s

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