msm: ipa: Fix race condition between shared memory

Protect the common shared wlan_comm_desc_list with
spin lock to avoid the race condition.

Change-Id: I02ef6c6b663340711e0e2f766424d642aaa8d7af
Acked-by: Mohammed Javid <mjavid@qti.qualcomm.com>
Signed-off-by: Utkarsh Saxena <usaxena@codeaurora.org>