[PATCH] USB: UHCI: change uhci_explen macro

This patch (as616) changed the uhci_explen macro in uhci-hcd.h so that
it now accepts the desired length, rather than length - 1 with special
handling for 0.  This also fixes a minor bug that would show up only
when a driver submits a 0-length bulk URB.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>