PCI: endpoint: Fix pci_epc_map map_size kerneldoc string

PCI: endpoint: Fix pci_epc_map map_size kerneldoc string

Because some endpoint controllers have requirements on the alignment of
the controller physical memory address that must be used to map a RC PCI
address region, the map PCI start address is not necessarily the desired
PCI base address to be mapped. This can result in map_pci_addr being
lower than pci_addr as documented. This results in map_size covering the
range map_pci_addr..pci_addr+pci_size.

The old text had the pci_addr twice instead of map_pci_addr..pci_addr,
so replace the erroneous kerneldoc string to reflect the actual range.

Link: https://lore.kernel.org/r/20241114161032.3046202-1-rick.wertenbroek@gmail.com
Signed-off-by: Rick Wertenbroek <rick.wertenbroek@gmail.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>