ASoC: wm_adsp: Support powering-up DSP without trying to load firmware

ASoC: wm_adsp: Support powering-up DSP without trying to load firmware

Add a flag to wm_adsp_power_up() that indicates whether it should attempt
to find and load firmware files.

This is to support DSPs that have built-in firmware that may already have
been patched (for example, by the BIOS). In that case the patch must not
be overwritten because that could corrupt the running firmware.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230815124826.5447-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>