pcie: fix section mismatch warning

Fix following section mismatch warning (when compiled with CONFIG_HOTPLUG=n):
WARNING: drivers/pci/built-in.o - Section mismatch: reference to .init.text:pcie_portdrv_probe from .data between 'pcie_portdrv' (at offset 0xe40) and 'pcie_portdrv_err_handler'

This warning was fixed by renaming pcie_portdrv to pcie_portdriver so we pass
the whitelist.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>