wifi: ath11k: dp: cleanup debug message

Merge the two debug messages into and fix them to follow the preferred style.

Also change the log level to ATH11K_DBG_DP_TX to match the filename.

Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.23

Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20230609142440.24643-11-kvalo@kernel.org