ALSA: emu10k1: factor out snd_emu10k1_compose_audigy_sendamounts()

Saves a bit of code duplication.

Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Link: https://lore.kernel.org/r/20230516093612.3536451-7-oswald.buddenhagen@gmx.de


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