audio: fix nominal volume channel (cosmetic)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Link: https://lore.kernel.org/r/20260211-cleanups-v1-1-e63c96572389@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

audio/audio-mixeng-be.c

@@ -1649,7 +1649,7 @@ static void audio_mixeng_backend_set_volume_out(AudioBackend *be, SWVoiceOut *sw
 
         sw->vol.mute = vol->mute;
         sw->vol.l = nominal_volume.l * vol->vol[0] / 255;
-        sw->vol.r = nominal_volume.l * vol->vol[vol->channels > 1 ? 1 : 0] /
+        sw->vol.r = nominal_volume.r * vol->vol[vol->channels > 1 ? 1 : 0] /
             255;
 
         if (k->volume_out) {