wma_self_peer_remove call wma_remove_peer with
del_vdev_req->self_mac_addr as peer mac address.
But wma_remove_peer still uses the pointer of self_mac_addr
to reference it after call wmi_unified_peer_delete_send.
Potentially the peer deleate event wma_peer_delete_handler
may come first and free the del_vdev_req memory.
In that case wma_remove_peer may access invalid memory,
wma_remove_objmgr_peer may fail to release the ref count on peer.
Fix by save del_vdev_req->self_mac_addr to local stack to
use it after send wmi_unified_peer_delete_send.
Change-Id: Idd9d765a13287144917d4774287da8b7ec4ea7ed
CRs-Fixed: 3815077
953d21b3e1