fft: free the plan on the invalid word length path #23623

Job	Run time
manifest-check	2m 48s
LP64-WIP	3m 51s
build-windows (mnfst, lnl)	7m 38s
build-windows (mnfst, imx8 imx8x)	9m 16s
build-windows (-d, mnfst, lnl)	8m 48s
build-windows (mnfst, ptl)	13m 58s
build-linux (mnfst, tgl-h)	3m 56s
build-linux (mnfst, ptl)	5m 20s
build-linux (mnfst, tgl)	4m 1s
build-linux (-d, mnfst, lnl)	4m 35s
build-linux (mnfst, wcl imx95)	5m 55s
build-windows (mnfst, mtl)	8m 55s
build-linux (mnfst, imx8 imx8x)	5m 10s
build-windows (mnfst, imx8m imx8ulp)	9m 56s
build-windows (mnfst, tgl)	8m 41s
build-linux (mnfst, mtl)	4m 16s
build-linux (mnfst, lnl)	4m 7s
build-windows (mnfst, tgl-h)	7m 24s
build-linux (mnfst, imx8m imx8ulp)	4m 52s
compare-linux-win	24s
	2h 3m 51s

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