ALSA: usb-audio: Don't override ignore_ctl_error value from the map

The mapping table may contain also ignore_ctl_error flag for devices
that are known to behave wild.  Since this flag always writes the
card's own ignore_ctl_error flag, it overrides the value already set
by the module option, so it doesn't follow user's expectation.
Let's fix the code not to clear the flag that has been set by user.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=206873
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200412081331.4742-3-tiwai@suse.deSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/usb/mixer.c

@@ -3106,7 +3106,7 @@ static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
 		if (map->id == state.chip->usb_id) {
 			state.map = map->map;
 			state.selector_map = map->selector_map;
-			mixer->ignore_ctl_error = map->ignore_ctl_error;
+			mixer->ignore_ctl_error |= map->ignore_ctl_error;
 			break;
 		}
 	}