msm: ipa: Fix deleting the routing entries

Make changes to delete the route entry even when the hdr/proc_ctx
handles are already freed. Otherwise the entry will be dangling.

Change-Id: Icbab6b96fa137c5214b37ea33c6203c5a54273ac
Signed-off-by: Chaitanya Pratapa <cpratapa@codeaurora.org>