KT-16535 'provideDelegate' convention is not supported in IR

Implement provideDelegate convention support.
NB delegate type now depends on 'provideDelegate' convention resolution.

compiler/testData/ir/irText/declarations/provideDelegate/differentReceivers.kt

@@ -0,0 +1,13 @@
+// WITH_RUNTIME
+
+class MyClass(val value: String)
+
+operator fun MyClass.provideDelegate(host: Any?, p: Any): String =
+        this.value
+
+operator fun String.getValue(receiver: Any?, p: Any): String =
+        this
+
+val testO by MyClass("O")
+val testK by "K"
+val testOK = testO + testK