[FIR] Fix incorrect updating of callable reference type in delegated property

... if the delegate happens to be a function call whose second
argument is a callable reference but not actually a provideDelegate
call.
The fix is to ensure that the call is _actually_ a desugared
provideDelegate call.

This fixes a CCE in a case where the delegate expression is a regular
function call and the second argument is a callable reference.

#KT-65165 Fixed

compiler/testData/codegen/box/delegatedProperty/callableReferenceAsSecondArgumentOfDelegate.kt

@@ -0,0 +1,23 @@
+// WITH_STDLIB
+// ISSUE: KT-65165
+
+import kotlin.properties.ReadOnlyProperty
+import kotlin.reflect.KProperty
+
+private class TransformedConfigPropertyString(
+    defaultValue: String,
+    private val transform: (String) -> Regex
+) : ReadOnlyProperty<SampleClass, Regex> {
+    override fun getValue(thisRef: SampleClass, property: KProperty<*>): Regex {
+        return transform("string")
+    }
+}
+
+class SampleClass {
+    val ignoreStringsRegex: Regex by TransformedConfigPropertyString("$^", String::toRegex)
+}
+
+fun box(): String {
+    SampleClass().ignoreStringsRegex
+    return "OK"
+}