basertpendpoint: Do not send events downstream when a packet is lost

As buffers are being marked with flag DISCONT it is a more accurate way
to known that we have lost data

Change-Id: I46d9cbecc904fc9626564917ac959e625063d308
basertpendpoint: Set jitterbuffer synchronization to synced

This type of synchronization keeps remote timestamps, this maintains
audio and video synced and spacing between frames is also kept.

Change-Id: Id4130c8a3b93d2fa078322775a130b8990069195
kmsutils: Do not handle GAP events

Buffers are already marked with DISCONT flag and do not have the risk
of being unsynced

Change-Id: I908ca9f1754b1c02212907d73a6d9ec788abcc00
kmsutils: Just start keyframe request when a flag is marked as discont

GAP marked buffers are generated to fill gaps, do not indicate that
a keyframe is required

Change-Id: Iba8a4f7293ffcfae65830c65d5b02ad1e85c968f
kmsutils: Add semicolons at end of macros lines to avoid indent warning

Change-Id: I2c37941c1364fe8a6a0fb76068d051a1df912f1f