cmocka: eq_iir and eq_fir: Fix test crash #21237

Job	Run time
LP64-WIP	3m 44s
manifest-check	52s
build-windows (imx8 imx8x imx8m imx8ulp)	9m 42s
build-windows (tgl tgl-h)	7m 27s
build-windows (mtl lnl)	7m 31s
build-windows (ptl)	6m 34s
build-windows (-d, lnl)	7m 11s
build-linux (mnfst, tgl tgl-h)	5m 26s
build-linux (zmain, imx8 imx8x imx8m imx8ulp)	6m 41s
build-linux (mnfst, mtl lnl)	5m 38s
build-linux (zmain, mtl lnl)	5m 36s
build-linux (-d, mnfst, lnl)	4m 21s
build-linux (mnfst, --all)	16m 7s
build-linux (zmain, tgl tgl-h)	5m 14s
build-linux (mnfst, ptl)	4m 18s
build-linux (mnfst, imx8 imx8x imx8m imx8ulp)	6m 31s
build-linux (zmain, ptl)	4m 37s
compare-linux-win	1m 54s
	1h 49m 24s

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