bluetooth: Add no volume control quirk for Thinkplus XT99

When this headset works in HFP/HSP profile, the input/output volume adjustment doesn't work if the headset is playing sth or capturing sth. Through the btmon log, we could see "+VGS" and "+VGM" were sent to headset and headset replied "command success", but the volume was not changed.

It is something like once the SCO connecton is built, the volume couldn't be changed by "+VGS" and "+VGM" commands. Here add a quirk for this headset, skip to set set_sink_volume and set_source_volume, after this change, the pulseaudio will apply the software volume adjustment to this headset in the HFP/HSP mode. This change doesn't impact A2DP volume adjustment for this headset.

Signed-off-by: Hui Wang hui.wang@canonical.com