msm: ipa3: fix packet handling for multiple buffers

Enable EOB event notification from GSI in order to receive completion
events on partial packets, which are split to multiple buffers.
This change is fixing few bugs in the handling of such a scenario.

CRs-Fixed: 1043511
Change-Id: I830dba8f4e47e3383b09639416fc704caa94cdf2
Acked-by: Ady Abraham <adya@qti.qualcomm.com>
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>