Support Comparable#compareTo for boxed primitive in redundant
boxing/unboxing analysis, along with CHECKCAST to java.lang.Comparable.
Note that we can do that for Float and Double, too, because
Float#compareTo(Float) and Double#compareTo(Double) are delegated to
Float#compare(float, float) and Double#compare(double, double),
respectively.
Fuse specialized comparison for integers with conditional jumps
if possible (both for Comparable#compareTo and Intrinsics#areEqual).
#KT-11959 Fixed
