Fixes win32/LabJackScaffold, timer configure without initial value.

If there's no initial value for a timer, trying to get the result of
setting an initial value fails, which causes the device to fail its
initialization.
Merge branch 'fix/labjackdevice-timer-init' into 'master'

Fixes LabJackScaffold, only get result of setting initial timer value if it was actually set.

+1: haizhouW, Julien Lenoir, Harald Scheirich

Merged-on: https://www.assembla.com/code/OpenSurgSim/git/merge_requests/1048184