Since rB298d5eb66916 [which was needed to update buttons with custom
property range functions correctly], using tab would always clamp
(hardmin/hardmax) properties which were using FLT_MAX / INT_MAX as range
in their property definitions.

The clamping of rB298d5eb66916 was copied over from rB9b7f44ceb56c
[where it was used for the softmin/softmax], and while the re-evaluation
of hardmin/hardmax is needed for custom property range functions, I
think the clamping should actually not take place.
There are many properties using FLT_MAX / INT_MAX etc. and while it
probably would be good to update these with ranges that make more sense

• not using FLT_MAX / INT_MAX would not have done the clamping here --

it seems wrong to clamp hard.