qcacmn: Return correct rx refill buf ring

In dp_rxdma_get_mon_buf_ring returns mac id index of
rx_refill_buf_ring array. But for targets with only one
pdev only the zeroth index is initialized. This will lead
to replenish failures in case of monitor mode when mon dest
process of lmac ring with mac id 1. So return only index 0 of
rx refill buf ring.

Change-Id: I03a7e19ea8d976e19fe6482aff0080dfa4d5ec45
CRs-Fixed: 2638655
1 file changed