Add lock to mute unmute of mic stream
Add lock to mute unmute of mic stream

This should alleviate a potential (or possibly an existing) problem if
mute is triggered while reading of the mic occurs.

MycroftAI/mycroft-core,MycroftAI/mycroft-core,Dark5ide/mycroft-core,forslund/mycroft-core,Dark5ide/mycroft-core,forslund/mycroft-core