[Wasm][NFC] Remove misleading default arguments from WasmKlibCheckers

They were unused anyway and suggested that there were situations where
empty versions of these arguments can be used, which no longer
seems to be the case.

Author: jmrtsh

compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/wasm/WasmKlibCheckers.kt

@@ -20,8 +20,8 @@ object WasmKlibCheckers {
     fun makeChecker(
         diagnosticReporter: IrDiagnosticReporter,
         configuration: CompilerConfiguration,
-        cleanFiles: List<SerializedIrFile> = listOf(),
-        exportedNames: ExportNamesMap = mapOf()
+        cleanFiles: List<SerializedIrFile>,
+        exportedNames: ExportNamesMap,
     ): IrVisitorVoid {
         return object : IrVisitorVoid() {
             private val diagnosticContext = JsKlibDiagnosticContext(configuration)