ASoC: Intel: avs: Include CPUID header at file scope

ASoC: Intel: avs: Include CPUID header at file scope

Commit

    cbe37a4d2b3c ("ASoC: Intel: avs: Configure basefw on TGL-based platforms")

includes the main CPUID header from within a C function.  This works by
luck and forbids valid refactoring inside that header.

Include the CPUID header at file scope instead.

Remove the COMPILE_TEST build flag so that the CONFIG_X86 conditionals can
be removed.  The driver gets enough compilation testing already on x86.

For clarity, refactor the CPUID(0x15) code into its own function without
changing any of the driver's logic.

Fixes: cbe37a4d2b3c ("ASoC: Intel: avs: Configure basefw on TGL-based platforms")
Suggested-by: Borislav Petkov <bp@alien8.de>		# CONFIG_X86 removal
Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Cezary Rojewski <cezary.rojewski@intel.com>
Link: https://lore.kernel.org/all/20250612234010.572636-3-darwi@linutronix.de