wifi: ath11k: wmi: cleanup error handling in ath11k_wmi_send_init_country_cmd()

The error handling doesn't follow the preferred style so fix that.

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/20230609142440.24643-7-kvalo@kernel.org