wifi: ath12k: delete the timer rx_replenish_retry during rmmod

The rx_replenish_retry timer is initialized in ath12k_core_alloc() when ath12k
module is loaded.  But rx_replenish_retry timer is not deleted anywhere in the
code.  It is supposed to be deleted when ath12k module is removed/unloaded.

Delete the timer rx_replenish_retry in ath12k_core_free().

Found during code review.

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.0-02903-QCAHKSWPL_SILICONZ-1

Signed-off-by: Hari Chandrakanthan <quic_haric@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/1685355238-3282-1-git-send-email-quic_haric@quicinc.com