wifi: ath12k: avoid unnecessary MSDU drop in the Rx error process

Currently, in the Rx error processing handler, once an MSDU drop is
detected, the subsequent MSDUs get unintentionally dropped due to the
previous drop flag being retained across all MSDU processing, leading
to the discarding of valid MSDUs. To resolve this issue, the drop flag
should be reset to false before processing each descriptor.

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.0.1-00029-QCAHKSWPL_SILICONZ-1

Signed-off-by: Karthikeyan Periyasamy <quic_periyasa@quicinc.com>
Acked-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://msgid.link/20240604062641.2956288-1-quic_periyasa@quicinc.com