xhci: clean up work to remove unused parameters for functions in xhci-mem.c

Some parameters are not used by functions in xhci-mem.c, just
remove it.

Changes compared to v1:
- Rebase to the latest usb-next branch

Signed-off-by: Lin Wang <lin.x.wang@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>