FIR2IR: Fix complex cases of smart cast expressions used as dispatch receiver

It might be not only <ExpressionWithSmartCast>(a).foo(), but also
id(<ExpressionWithSmartCast>(a)).foo() and many other cases

compiler/testData/ir/irText/expressions/variableAsFunctionCall.fir.kt.txt

@@ -23,12 +23,12 @@ fun test4(ns: String?): String? {
       val tmp0_safe_receiver: String? = ns
       when {
         EQEQ(arg0 = tmp0_safe_receiver, arg1 = null) -> null
-        else -> tmp0_safe_receiver.k()
+        else -> tmp0_safe_receiver /*as String */.k()
       }
     }
     when {
       EQEQ(arg0 = tmp1_safe_receiver, arg1 = null) -> null
-      else -> tmp1_safe_receiver.invoke()
+      else -> tmp1_safe_receiver /*as Function0<String> */.invoke()
     }
   }
 }