emu_lock locks the card's registers, but that's necessary only for
multi-register access, incl. read-modify-write cycles.
Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Link: https://lore.kernel.org/r/20230428095941.1706278-3-oswald.buddenhagen@gmx.deSigned-off-by: Takashi Iwai <tiwai@suse.de>