usb: host: xhci-plat: omit shared hcd if either root hub has no ports

Activate the just added extension for xhci-plat and omit the shared
hcd if either of the root hubs has no ports.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220511220450.85367-6-mathias.nyman@linux.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>