Safely check for suspend function parent

The issue here is that the function can be in unlowered file, and
thus its parent package fragment and not class.

 #KT-49317 Fixed

compiler/tests-gen/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java

@@ -7914,6 +7914,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
             runTest("compiler/testData/codegen/box/coroutines/kt46813.kt");
         }
 
+        @TestMetadata("kt49317.kt")
+        public void testKt49317() throws Exception {
+            runTest("compiler/testData/codegen/box/coroutines/kt49317.kt");
+        }
+
         @TestMetadata("kt49645.kt")
         public void testKt49645() throws Exception {
             runTest("compiler/testData/codegen/box/coroutines/kt49645.kt");