FIR: Adjust testData for spec tests: discrepancy in DEBUG_INFO_CALL format

In old FE, there are fake overrides rendered, while in FIR there are
real declarations

compiler/tests-spec/testData/diagnostics/linked/overload-resolution/building-the-overload-candidate-set-ocs/call-with-an-explicit-receiver/p-6/pos/1.1.fir.kt

@@ -0,0 +1,91 @@
+// !LANGUAGE: +NewInference
+// !DIAGNOSTICS: -UNUSED_VARIABLE -ASSIGNED_BUT_NEVER_ACCESSED_VARIABLE -UNUSED_VALUE -UNUSED_PARAMETER -UNUSED_EXPRESSION
+// SKIP_TXT
+
+/*
+ * KOTLIN DIAGNOSTICS SPEC TEST (POSITIVE)
+ *
+ * SPEC VERSION: 0.1-268
+ * PLACE: overload-resolution, building-the-overload-candidate-set-ocs, call-with-an-explicit-receiver -> paragraph 6 -> sentence 1
+ * RELEVANT PLACES: overload-resolution, c-level-partition -> paragraph 1 -> sentence 1
+ * overload-resolution, building-the-overload-candidate-set-ocs, call-with-an-explicit-receiver -> paragraph 3 -> sentence 1
+ * overload-resolution, building-the-overload-candidate-set-ocs, call-with-an-explicit-receiver -> paragraph 2 -> sentence 1
+ * overload-resolution, receivers -> paragraph 7 -> sentence 2
+ * overload-resolution, receivers -> paragraph 7 -> sentence 3
+ * NUMBER: 1
+ * DESCRIPTION: sets of non-extension member callables only
+ */
+
+package tests.test2
+
+// TESTCASE NUMBER: 1
+open class Case1() {
+    companion object foo {
+        operator fun invoke() {}
+    }
+
+    val propVal: Int = 1
+    val propVar: Int = 1
+    fun function() {}
+    val markerObj = object : Marker {}
+
+    fun innerFun() {
+        foo()
+        Case1.foo()
+        propVal()
+        this.propVal()
+        propVar()
+        this.propVar()
+        function()
+        this.function()
+        markerObj()
+        this.markerObj()
+    }
+
+    operator fun Int.invoke() {}
+
+    inner class InnerClass {
+
+        fun innerClassFun() {
+            foo()
+            Case1.foo()
+
+            propVal()
+            this@Case1.propVal()
+
+            propVar()
+            this@Case1.propVar()
+
+            function()
+            this@Case1.function()
+
+            markerObj()
+            this@Case1.markerObj()
+        }
+    }
+}
+
+interface Marker {
+    operator fun invoke() {}
+}
+
+class ExtendCase1() : Case1() {
+
+    fun extFun() {
+        foo()
+        Case1.foo()
+        propVal()
+        this.propVal()
+        propVar()
+        this.propVar()
+        function()
+        this.function()
+        markerObj()
+        this.markerObj()
+    }
+}
+
+fun case6() {
+    Case1.invoke()
+    Case1.foo()
+}