PCI: Make pci_enable_ptm() private

This interface:

  int pci_enable_ptm(struct pci_dev *dev, u8 *granularity);

is only used in drivers/pci/ and does not need to be seen by the rest of
the kernel.  Move it to drivers/pci/pci.h so it's private to the PCI
subsystem.

Link: https://lore.kernel.org/r/20190724233848.73327-11-skunberg.kelsey@gmail.com
Signed-off-by: Kelsey Skunberg <skunberg.kelsey@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/pci.h

@@ -551,8 +551,11 @@ static inline void pcie_ecrc_get_policy(char *str) { }
 
 #ifdef CONFIG_PCIE_PTM
 void pci_ptm_init(struct pci_dev *dev);
+int pci_enable_ptm(struct pci_dev *dev, u8 *granularity);
 #else
 static inline void pci_ptm_init(struct pci_dev *dev) { }
+static inline int pci_enable_ptm(struct pci_dev *dev, u8 *granularity)
+{ return -EINVAL; }
 #endif
 
 struct pci_dev_reset_methods {

include/linux/pci.h

@@ -1561,13 +1561,6 @@ static inline bool pci_aer_available(void) { return false; }
 
 bool pci_ats_disabled(void);
 
-#ifdef CONFIG_PCIE_PTM
-int pci_enable_ptm(struct pci_dev *dev, u8 *granularity);
-#else
-static inline int pci_enable_ptm(struct pci_dev *dev, u8 *granularity)
-{ return -EINVAL; }
-#endif
-
 void pci_cfg_access_lock(struct pci_dev *dev);
 bool pci_cfg_access_trylock(struct pci_dev *dev);
 void pci_cfg_access_unlock(struct pci_dev *dev);