In order to support flow overide feature,
AST table has to be split between RxPCU and DDR.
With this split, RX monitor cannot make use of
ast_index to fetch peer as it is not from DDR.
So make use of sw_peer_id to fetch peer.
This sw_peer_id is derived from RX_MPDU_STAT_START_TLV
Remove the spinlock on unsused variable i.e ast->lock.
These changes were overwritten by monitor segregation
effort, hence bringing back again.
Change-Id: I339f4296562e3b4dfd6f3a71102385e395f00268
CRs-Fixed: 3108200
d70b48ed27