pci: fix new kernel-doc warning in pci.c

Fix new kernel-doc warning in pci.c:

  Warning(drivers/pci/pci.c:3259): No description found for parameter 'mps'
  Warning(drivers/pci/pci.c:3259): Excess function parameter 'rq' description in 'pcie_set_mps'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/pci/pci.c

@@ -3250,7 +3250,7 @@ int pcie_get_mps(struct pci_dev *dev)
 /**
  * pcie_set_mps - set PCI Express maximum payload size
  * @dev: PCI device to query
- * @rq: maximum payload size in bytes
+ * @mps: maximum payload size in bytes
  *    valid values are 128, 256, 512, 1024, 2048, 4096
  *
  * If possible sets maximum payload size