Native: quick fix lazy init boxing issue

FileInitializersLowering shouldn't expect codegen to initialize field
statically if constant literal is going to be boxed

^KT-48364

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/FileInitializersLowering.kt

@@ -20,6 +20,7 @@ import org.jetbrains.kotlin.ir.builders.declarations.buildFun
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.IrBlockBody
 import org.jetbrains.kotlin.ir.expressions.IrConst
+import org.jetbrains.kotlin.ir.expressions.IrConstKind
 import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
 import org.jetbrains.kotlin.ir.util.SYNTHETIC_OFFSET
 import org.jetbrains.kotlin.ir.util.hasAnnotation
@@ -113,5 +114,10 @@ internal class FileInitializersLowering(val context: Context) : FileLoweringPass
         get() = hasNonConstInitializer || needsGCRegistration(context)
 
     private val IrField.hasNonConstInitializer: Boolean
-        get() = initializer?.expression.let { it != null && it !is IrConst<*> }
+        get() {
+            val it = initializer?.expression ?: return false
+            if (it !is IrConst<*>) return true
+            if (it.kind != IrConstKind.Null && it.type != this.type) return true // Might be boxed, so codegen won't treat it as const.
+            return false
+        }
 }