This fixes the COM interface over USB HID to the point where
it can establish and maintain solid communications with the UAVObject
Browser in the GCS.
Tested only on Linux. The USB HID interface is still disabled for now
until it is tested successfully by a wider group.
Edit telemetry.c and set ALLOW_HID_TELEMETRY to 1 to enable telemetry
over the USB HID interface and report your results in the forum.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@656 ebee16cc-31ac-478f-84a7-5cbb03baadba
