ath10k: add back enum ath10k_bus

Commit 3a0861fffd ("ath10k: remove ath10k_bus") removed enum ath10k_bus
because it was not used for anything at the time. But now it's needed for for
retrieving the right calibration data file so add it back. Only new addition is
ath10k_bus_str().

Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath10k/pci.c

@@ -2435,6 +2435,7 @@ static int ath10k_pci_probe(struct pci_dev *pdev,
 	u32 chip_id;
 
 	ar = ath10k_core_create(sizeof(*ar_pci), &pdev->dev,
+				ATH10K_BUS_PCI,
 				&ath10k_pci_hif_ops);
 	if (!ar) {
 		dev_err(&pdev->dev, "failed to allocate core\n");