usb: xhci: Enable LPM for VIA LABS VL805

usb: xhci: Enable LPM for VIA LABS VL805

This PCIe controller chip is used on the Raspberry Pi 4 and multiple
adapter cards. There is no publicly available documentation for the
chip, yet both the downstream RPi4 kernel and the controller cards
support/advertise LPM support.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200312144517.1593-5-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>