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/codegen/box/smartCasts/complexExplicitReceiver.kt

@@ -0,0 +1,26 @@
+abstract class A {
+    abstract fun o(): String
+}
+
+interface B {
+    fun k(): String
+}
+
+fun <T> id(x: T): T = x
+
+fun foo(a: A?): String {
+    if (a is B) {
+        return id(a).o() + a!!.k()
+    }
+
+    return "fail"
+}
+
+class Impl : A(), B {
+    override fun o(): String = "O"
+    override fun k(): String = "K"
+}
+
+fun box(): String {
+    return foo(Impl())
+}