Implement special desugaring for numeric comparisons in PSI2IR

This introduces the following IR built-in functions required for proper
implementation of the number comparisons:

- ieee754Equals(T, T): Boolean,
    for each T in {Float?, Double?}

- less(T, T): Boolean
  lessOrEqual(T, T): Boolean
  greater(T, T): Boolean
  greaterOrEqual(T, T): Boolean
    for each T in {Int, Long, Float, Double}

compiler/testData/ir/irText/expressions/floatingPointComparisons/floatingPointLess.kt

@@ -0,0 +1,10 @@
+fun test1d(x: Double, y: Double) = x < y
+fun test2d(x: Double, y: Any) = y is Double && x < y
+fun test3d(x: Any, y: Any) = x is Double && y is Double && x < y
+
+fun test1f(x: Float, y: Float) = x < y
+fun test2f(x: Float, y: Any) = y is Float && x < y
+fun test3f(x: Any, y: Any) = x is Float && y is Float && x < y
+
+fun testFD(x: Any, y: Any) = x is Float && y is Double && x < y
+fun testDF(x: Any, y: Any) = x is Double && y is Float && x < y