ALSA: scarlett2: Add minimum firmware version check

Early firmware for the Scarlett Gen 4 devices has sufficient
differences that it is better to enforce a minimum firmware version
than to try and work around those differences. Add a minimum firmware
version field to the device info struct, and display a message if the
firmware version is too old. Only create the Firmware Version and MSD
(optional) controls in this case.

Signed-off-by: Geoffrey D. Bennett <g@b4.vu>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/5455a7e54bda81556066abd7f761b10e9c5f8a16.1703612638.git.g@b4.vu