Build: Fix sign comparison in governancemodel.cpp
Build: Fix sign comparison in governancemodel.cpp

`name.toUtf8().size()` is already an `int`, so the cast needs to be for
`PROP_NAME_MAX_SIZE`, which is a `size_t`

PIVX-Project/PIVX,PIVX-Project/PIVX,PIVX-Project/PIVX,PIVX-Project/PIVX,PIVX-Project/PIVX,PIVX-Project/PIVX,PIVX-Project/PIVX,PIVX-Project/PIVX,PIVX-Project/PIVX