sensorhandler: Support 0 value for thresholds

Currently the threshold value is considered present if its
value is not equal 0. Therefore it is not possible to support
thresholds with a 0 value.
As special IEEE floating point values were added to the interface
it is now possible to represent an unset threshold as 'NaN'.
Consider a threshold present if it is finite (i.e. not NaN or
infinity) as infinity is also not a valid value.

Signed-off-by: Konstantin Aladyshev <aladyshev22@gmail.com>
Change-Id: Ifc4f70b840658b96a70ccd43126de67f873af38c
1 file changed