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
Change-Id: Ib2a003a2640fded3287c318d2ad59fd3127af9b6
CRs-fixed: 3004363