Handle alternate status values.

Some carriers use sendrecv to indicate a call in a conference is active,
and sendonly to indicate that the remote party has held the call.
Adding support for these status values.

This ensures that remotely held calls for these carriers are set to held.

Test: Manual
Bug: 33272103
Change-Id: I4a950c4e143d5ac396b30569dbda0b1cf4e92a3e