ASoC: Intel: sof_sdw: correct mach_params->dmic_num #7031

Job	Run time
GCC static -fanalyzer	3m 42s
GCC build arm64	17m 30s
GCC build arm64 allmodconfig	1m 37s
Clang build x86_64	4m 10s
GCC build i386	15m 2s
GCC build X86_64	20m 15s
GCC build X86_64 with W=1	2m 34s
GCC build X86_64 with W=1 allmodconfig	1m 36s
Sparse check	2m 40s
	1h 9m 6s

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