fold-const: Handle BITINT_TYPE in range_check_type

fold-const: Handle BITINT_TYPE in range_check_type

When discussing PR111369 with Andrew Pinski, I've realized that
I haven't added BITINT_TYPE handling to range_check_type.  Right now
(unsigned) max + 1 == (unsigned) min for signed _BitInt,l so I think we
don't need to do the extra hops for BITINT_TYPE (though possibly we don't
need them for INTEGER_TYPE either in the two's complement word and we don't
support anything else, though I really don't know if Ada or some other
FEs don't create weird INTEGER_TYPEs).

2023-09-12  Jakub Jelinek  <jakub@redhat.com>

	* fold-const.cc (range_check_type): Handle BITINT_TYPE like
	OFFSET_TYPE.