ALSA: hda: cs35l41: Prevent firmware load if SPI speed too low

ALSA: hda: cs35l41: Prevent firmware load if SPI speed too low

Some laptops without _DSD have the SPI speed set very low in the BIOS.
Since the SPI controller uses this speed as its max speed, the SPI
transactions are very slow. Firmware download writes to many registers,
and if the SPI speed is too slow, it can take a long time to download.
For this reason, disable firmware loading if the maximum SPI speed is
too low. Without Firmware, audio playback will work, but the volume
will be low to ensure safe operation of the CS35L41.

Signed-off-by: Stefan Binding <sbinding@opensource.cirrus.com>
Cc: <stable@vger.kernel.org> # v6.7+
Link: https://lore.kernel.org/r/20231221132518.3213-3-sbinding@opensource.cirrus.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>