xhci: Remove dead code in xhci_move_dequeue_past_td()

xhci: Remove dead code in xhci_move_dequeue_past_td()

This codepath is trivially dead, since the function is never called with
a non-NULL td (the only callsite is immediately preceded by a NULL guard).

[remove unused label 'deq_found' -Mathias]

Signed-off-by: Hector Martin <marcan@marcan.st>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20240626124835.1023046-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>