kselftest/alsa: pcm - move more configuration to configuration files

Obtain all test parameters from the configuration files. The defaults
are defined in the pcm-test.conf file. The test count and parameters
may be variable per specific hardware.

Also, handle alt_formats field now (with the fixes in the format loop).
It replaces the original "automatic" logic which is not so universal.

The code may be further extended to skip various tests based
on the configuration hints, if the exact PCM hardware parameters
are not available for the given hardware.

Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221208-alsa-pcm-test-hacks-v4-2-5a152e65b1e1@kernel.org


Signed-off-by: Takashi Iwai <tiwai@suse.de>