msm: ipc: Send REMOVE_CLIENT message when a server port is closed

When the server port is closed, only REMOVE_SERVER message is sent. If
the same port is used as a client port prior to the server registration,
then the IPC Router in the remote subsystem does not clean up the client
information associated with that port. This leads to memory leak in the
remote subsystem.

When the server exits and closes the port, IPC Router has to send both
REMOVE_SERVER and REMOVE_CLIENT messages. This ensures that the
IPC Router in the remote subsystem cleans up both the client and server
information associated with that port.

CRs-Fixed: 434981
Change-Id: I1d59aa773398d10dd5c648969b9da2e1cf481d24
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org>