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