ath11k: PCI changes to support WCN6750

In order to add the support for WCN6750 in ATH11K , it is
required to move certain PCI definitions to the header file.
As a result, add ATH11K_PCI_* prefix to these definitions.

Also, change the scope of certain PCI APIs that are required
to enable WCN6750 from static to global.

Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-01720.1-QCAHSPSWPL_V1_V2_SILICONZ_LITE-1
Tested-on: QCN9074 hw1.0 PCI WLAN.HK.2.5.0.1-01100-QCAHKSWPL_SILICONZ-1
Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.4.0.1-00192-QCAHKSWPL_SILICONZ-1

Signed-off-by: Manikanta Pubbisetty <quic_mpubbise@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20220328055714.6449-2-quic_mpubbise@quicinc.com