Add diagnostics for get/set methods of property delegate

compiler/testData/diagnostics/tests/delegatedProperty/twoGetMethods.kt

@@ -0,0 +1,15 @@
+class A {
+    val c: Int by <!DELEGATE_SPECIAL_FUNCTION_NONE_APPLICABLE!>Delegate()<!>
+}
+
+class Delegate {
+    fun get(t: Int, p: String): Int {
+        t.equals(p) // to avoid UNUSED_PARAMETER warning
+        return 1
+    }
+
+    fun get(t: String, p: String): Int {
+        t.equals(p) // to avoid UNUSED_PARAMETER warning
+        return 1
+    }
+}