ALSA: emu10k1: use the right lock in snd_emu10k1_shared_spdif_put()

The function does read-modify-write cycles on the card's registers, and
doesn't access mutable members of the emu data structure.

I suppose this might have been a mixup due to the lock names being
logically swapped.

Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Link: https://lore.kernel.org/r/20230428095941.1706278-4-oswald.buddenhagen@gmx.de


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