We used a hardware timer locally in the RPI USB driver because a timer
connection was not precise enough to fullfill the host controllers
requirements.
With the modern timer connection interface, however, reading out time at
a connection is microseconds precise and we can remove the local timer.
But we cannot use the same timer connection for doing legacy-interface
stuff like usleep (currently used in LX kit) and modern-interface stuff
like curr_time. Thus, we open two connections for now.
Ref #2400
47dc708887