msm: ipa: send filter notify req when client disconnects

IPA Q6 needs to know when the client pipe disconnects
to clean up call related settings. Make a change to
send filter notify req with filter index len as 0.

Change-Id: I989eed2e04156b4f6e193dce0e8e71d1f588e749
Acked-by: Chaitanya Pratapa <cpratapa@qti.qualcomm.com>
Signed-off-by: Utkarsh Saxena <usaxena@codeaurora.org>