wifi: ath12k: Refactor RX TID buffer cleanup into helper function

wifi: ath12k: Refactor RX TID buffer cleanup into helper function

Introduce ath12k_dp_rx_tid_cleanup() to handle RX TID buffer
unmapping and freeing. This replaces duplicated cleanup logic
across multiple code paths.

This improves code maintainability and avoids redundancy in
buffer cleanup operations.

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: Nithyanantham Paramasivam <nithyanantham.paramasivam@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20250806111750.3214584-4-nithyanantham.paramasivam@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>