ASoC: SDCA: support Q7.8 volume format #7909

Job	Run time
Sparse check	3m 37s
GCC static -fanalyzer	4m 21s
GCC build X86_64 with W=1	2m 0s
GCC build arm64 allmodconfig	3m 55s
GCC build X86_64 with W=1 allmodconfig	1m 43s
GCC build i386	16m 42s
GCC build X86_64	25m 1s
Clang build x86_64	2m 9s
GCC build arm64	24m 11s
	1h 23m 39s

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