K2: unwrap flexible types while determining function type kind

#KT-67264 Fixed

(cherry picked from commit 9863d7534e3638d10b5d7d12d7c2770642902eab)
diff --git a/compiler/fir/providers/src/org/jetbrains/kotlin/fir/types/ConeInferenceContext.kt b/compiler/fir/providers/src/org/jetbrains/kotlin/fir/types/ConeInferenceContext.kt
index ca07a87..acc17d6 100644
--- a/compiler/fir/providers/src/org/jetbrains/kotlin/fir/types/ConeInferenceContext.kt
+++ b/compiler/fir/providers/src/org/jetbrains/kotlin/fir/types/ConeInferenceContext.kt
@@ -569,7 +569,7 @@
 
     override fun KotlinTypeMarker.functionTypeKind(): FunctionTypeKind? {
         require(this is ConeKotlinType)
-        return this.functionTypeKind(session)
+        return (this.lowerBoundIfFlexible() as ConeClassLikeType).functionTypeKind(session)
     }
 
     override fun getNonReflectFunctionTypeConstructor(parametersNumber: Int, kind: FunctionTypeKind): TypeConstructorMarker {
diff --git a/compiler/testData/diagnostics/tests/suspendConversion/suspendConversionForLambdaList.fir.kt b/compiler/testData/diagnostics/tests/suspendConversion/suspendConversionForLambdaList.fir.kt
deleted file mode 100644
index 43a2e99..0000000
--- a/compiler/testData/diagnostics/tests/suspendConversion/suspendConversionForLambdaList.fir.kt
+++ /dev/null
@@ -1,20 +0,0 @@
-// ISSUE: KT-67264
-// WITH_STDLIB
-
-// FILE: MyList.java
-public class MyList<T> {
-    void addAll(Iterable<? extends T> elements) {
-    }
-}
-
-// FILE: main.kt
-fun foo() {
-    val anys = listOf(Any(), Any(), Any())
-    MyList<suspend () -> Any>().addAll(
-        anys.map { any ->
-            <!ARGUMENT_TYPE_MISMATCH!>{
-                any
-            }<!>
-        }
-    )
-}
diff --git a/compiler/testData/diagnostics/tests/suspendConversion/suspendConversionForLambdaList.kt b/compiler/testData/diagnostics/tests/suspendConversion/suspendConversionForLambdaList.kt
index 1a67556..10d2d12 100644
--- a/compiler/testData/diagnostics/tests/suspendConversion/suspendConversionForLambdaList.kt
+++ b/compiler/testData/diagnostics/tests/suspendConversion/suspendConversionForLambdaList.kt
@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 // ISSUE: KT-67264
 // WITH_STDLIB