PCI: Fix comment typo, remove unnecessary !! in pci_is_pcie()

Use normal kernel-doc "Returns:" instead of "retrun"
Assignment to bool is always 1 or 0 so the !! isn't necessary.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

include/linux/pci.h

@@ -1749,11 +1749,11 @@ static inline int pci_pcie_cap(struct pci_dev *dev)
  * pci_is_pcie - check if the PCI device is PCI Express capable
  * @dev: PCI device
  *
- * Retrun true if the PCI device is PCI Express capable, false otherwise.
+ * Returns: true if the PCI device is PCI Express capable, false otherwise.
  */
 static inline bool pci_is_pcie(struct pci_dev *dev)
 {
-	return !!pci_pcie_cap(dev);
+	return pci_pcie_cap(dev);
 }
 
 /**