KT-15871 Unnecessary boxing for equality operator on inlined primitive values

Allow kotlin.jvm.internal.Intrinsics#areEqual for boxed values.
Rewrite to primitive equality.

NB we can't do that for Float and Double, because java.lang.Float#equals
and java.lang.Double#equals behave differently from primitive equality comparisons.

compiler/testData/codegen/bytecodeText/boxingOptimization/boxingAndEquals.kt

@@ -0,0 +1,17 @@
+// https://youtrack.jetbrains.com/issue/KT-15871
+
+// FILE: Test.kt
+
+fun getAndCheckInt(a: Int, b: Int) =
+        getAndCheck({ a }, { b })
+
+// @TestKt.class:
+// 0 valueOf
+// 0 Value
+// 0 areEqual
+
+// FILE: Inline.kt
+inline fun <T> getAndCheck(getFirst: () -> T, getSecond: () -> T) =
+        getFirst() == getSecond()
+
+