ALSA: snd-usb-caiaq: Increase version number to 1.3.12

Indicates fixes affecting control messages and switching of input mode
on Audio 8 DJ and Audio 4 DJ.

Signed-off-by: Mark Hills <mark@pogo.org.uk>
Acked-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>