[gst] Support media.role in event configuration file
[gst] Support media.role in event configuration file

By default gst plugin use media.role=media.
When another media.role is needed it can be configured in event file in /usr/share/ngfd/events.d/

For example:
sound.stream.media.role = mymedia

jusa/ngfd,android-808/ngfd,jusa/ngfd,jusa/ngfd,android-808/ngfd