Pass full range to build_* in range-op-float.cc

Pass full range to build_* in range-op-float.cc

The build_<relop> helper functions in range-op-float.cc take the
actual value from the operand's endpoint, but this value could be
deduced from the operand itself therefore cleaning up the call site.
This also reduces the potential of mistakenly passing the wrong bound.

No functional changes.

Regstrapped on x86-64 Linux, plus I ran selftests for
-ffinite-math-only.

gcc/ChangeLog:

	* range-op-float.cc (build_le): Accept frange instead of number.
	(build_lt): Same.
	(build_ge): Same.
	(build_gt): Same.
	(foperator_lt::op1_range): Pass full range to build_*.
	(foperator_lt::op2_range): Same.
	(foperator_le::op1_range): Same.
	(foperator_le::op2_range): Same.
	(foperator_gt::op1_range): Same.
	(foperator_gt::op2_range): Same.
	(foperator_ge::op1_range): Same.
	(foperator_ge::op2_range): Same.