ALSA: ymfpci: Use register macro in place of integer literal

The macro for said register already exists, so just use it, to make the
code more readable.

Signed-off-by: Tasos Sahanidis <tasos@tasossah.com>
Link: https://lore.kernel.org/r/20230329043918.179352-1-tasos@tasossah.com


Signed-off-by: Takashi Iwai <tiwai@suse.de>