wifi: ath12k: remove monitor handling from ath12k_dp_rx_deliver_msdu()

wifi: ath12k: remove monitor handling from ath12k_dp_rx_deliver_msdu()

ath12k_dp_rx_deliver_msdu() currently includes logic related to
monitor mode handling. This code was inherited from the ath11k driver,
where a single rx handler was used for both regular and monitor mode
packets. In ath12k, however, monitor mode packets are handled separately
via ath12k_dp_mon_rx_deliver_msdu(), which contains all the necessary
monitor-specific logic. Therefore, monitor-related checks and operations
in ath12k_dp_rx_deliver_msdu() are no longer needed. Remove this dead code
to simplify the rx path and avoid unnecessary per-packet checks.

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 <praneesh.p@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20250605054438.1855365-1-praneesh.p@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>