This patch (as1274) simplifies the counting of transaction-error
retries.  Now we will count up from 0 to QH_XACTERR_MAX instead of
down from QH_XACTERR_MAX to 0.

The patch also fixes a small bug: qh->xacterr was not getting
initialized for interrupt endpoints.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NMatthijs Kooijman <matthijs@stdin.nl>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>