Fix compilation warning for converting negative integer constant to unsigned. (#19013)
When compiling, Visual Studio gives two compiler warnings in the sysmath.c file about FPILOGB0/-
2147483648 being converted into an unsigned integer.
The standard library math.h states that FPILOGB0 be INT_MIN, so I replaced -
2147483648 with the INT_MIN macro so the behavior is much more clear as well as stifling the compiler warnings.
Changes tested manually and automatically.
Co-authored-by: pi1024e <49824824+pi1024e@users.noreply.github.com>