Do not report "unused receiver" on operator and infix functions

So #KT-16340 Fixed

idea/testData/inspectionsLocal/unusedReceiverParameter/operator.kt

@@ -0,0 +1,14 @@
+// PROBLEM: none
+
+class Test(val test: Int) {
+    fun foo() = test
+}
+
+// Receiver unused but still inapplicable (operator!)
+operator fun <caret>Test.invoke(x: Int, y: Int) = Test(x + y)
+
+
+fun main(args: Array<String>) {
+    val x = Test(0)(1, 2)
+    x.foo()
+}