usb: xhci-pci: Add DM_FLAG_OS_PREPARE flag

The PCIe bus the controller is connected to might need to be removed
prior the handover. Make sure xhci-pci is also removed so as to avoid
unexpected timeouts or hangs.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Matthias Brugger <mbrugger@suse.com>
1 file changed