Fix IrFunction.isEmptyArray implementation

The previous one was incorrect for K1 since parent of top-level function
is `IrClass`, not `IrPackageFragment`.

The change is non-functional, K1 still worked correctly, but had to do
some extra work when inlining `emptyArray` calls and produces less
performant bytecode.

compiler/testData/codegen/box/script/syntheticJavaPropertyInScript.jvm_abi.txt

@@ -1,29 +1,4 @@
 MODULE main
-	CLASS MainKt.class
-		Annotation: class.invisibleAnnotations
-			K1
-				@Lkotlin/jvm/internal/SourceDebugExtension;( value: #{ SMAP
-				main.kt
-				Kotlin
-				*S Kotlin
-				*F
-				+ 1 main.kt
-				MainKt
-				+ 2 ArrayIntrinsics.kt
-				kotlin/ArrayIntrinsicsKt
-				*L
-				1#1,50:1
-				26#2:51
-				*S KotlinDebug
-				*F
-				+ 1 main.kt
-				MainKt
-				*L
-				42#1:51
-				*E
-				 } )
-			K2
-				---
 	CLASS Script.class
 		CLASS METADATA
 			K1