Leave boxing for compareTo/areEqual methods for inline classes

Inline classes can override methods and thus introduce side effects

compiler/testData/codegen/box/inlineClasses/conformToComparableAndCallInterfaceMethod.kt

@@ -0,0 +1,17 @@
+// !LANGUAGE: +InlineClasses
+// IGNORE_BACKEND: JVM_IR
+
+inline class Foo(val x: Int) : Comparable<Foo> {
+    override fun compareTo(other: Foo): Int {
+        return 10
+    }
+}
+
+fun box(): String {
+    val f1 = Foo(42)
+    val ff1: Comparable<Foo> = f1
+
+    if (ff1.compareTo(f1) != 10) return "Fail"
+
+    return "OK"
+}