ALSA: hda/cs35l56: Always power-up and start cs_dsp

Always call cs_dsp_power_up() and cs_dsp_run() in
cs35l56_hda_fw_load() even if there aren't any firmware files
to download. Also, if there aren't any firmware files to
download there is no need to do cs35l56_firmware_shutdown() and
cs35l56_system_reset().

If there aren't any firmware files there's no need to write
anything to the CS35L56 registers to make it work - it will
already be running the ROM firmware. So it's not strictly
necessary to start cs_dsp.

But it's perfectly ok to call cs_dsp_power_up() and
cs_dsp_run() without downloading any firmware. This avoids
having to support a state where audio is playing but cs_dsp
is not running.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230731165726.7940-5-rf@opensource.cirrus.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>