buf: use API for iteration bsource_list in components #416

Job	Run time
LP64-WIP	3m 40s
build-windows (imx8 imx8x imx8m imx8ulp)	7m 40s
build-linux (mnfst, imx8 imx8x imx8m imx8ulp)	6m 16s
build-windows (mtl)	6m 11s
manifest-check	46s
build-windows (tgl tgl-h)	6m 7s
build-linux (mnfst, mtl)	4m 22s
build-windows (-d, mtl)	5m 35s
build-linux (mnfst, lnl)	4m 12s
build-linux (mnfst, tgl tgl-h)	5m 13s
build-linux (zmain, imx8 imx8x imx8m imx8ulp)	5m 44s
build-linux (zmain, mtl)	4m 32s
build-linux (zmain, lnl)	4m 23s
build-linux (zmain, tgl tgl-h)	5m 28s
build-linux (-d, mnfst, mtl)	4m 22s
build-linux (mnfst, --all)	10m 18s
compare-linux-win	24s
	1h 25m 13s

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