[flang] Fold OUT_OF_RANGE()

Fold the F'2018 intrinsic function OUT_OF_RANGE(), which returns .TRUE.
when a conversion of an integer or real value to an integer or real type
would yield an overflow or (for real->integer only) invalid operand
exception.  Test all type combinations, with both rounding possibilities
for the real->integer cases.

Differential Revision: https://reviews.llvm.org/D159038