wifi: ath12k: Avoid code duplication in monitor ring processing

wifi: ath12k: Avoid code duplication in monitor ring processing

The current implementation processes the monitor destination ring using
two separate functions, ath12k_dp_mon_srng_process() for standalone
monitor mode and ath12k_dp_mon_rx_process_stats() for statistics.
However, both functions contain same code which performs monitor ring
reaping and skb data processing. To eliminate redundancy, remove the
duplicate code and use a single function to handle both the cases.

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.3.1-00173-QCAHKSWPL_SILICONZ-1
Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3

Signed-off-by: P Praneesh <quic_ppranees@quicinc.com>
Link: https://patch.msgid.link/20241223060132.3506372-5-quic_ppranees@quicinc.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>