JVM_IR: expect unboxed return value from suspend default stubs

#KT-47206 Fixed

compiler/testData/codegen/box/coroutines/inlineClasses/direct/defaultStub.kt

@@ -0,0 +1,21 @@
+// WITH_RUNTIME
+// KJS_WITH_FULL_RUNTIME
+import kotlin.coroutines.*
+
+fun builder(c: suspend () -> Unit) {
+    c.startCoroutine(Continuation(EmptyCoroutineContext) {
+        it.getOrThrow()
+    })
+}
+
+inline class IC(val s: String)
+
+suspend fun foo(x: String = "OK") = IC(x)
+
+fun box(): String {
+    var res = ""
+    builder {
+        res = foo().s
+    }
+    return res
+}

compiler/testData/codegen/box/coroutines/inlineClasses/resume/defaultStub.kt

@@ -0,0 +1,17 @@
+// WITH_RUNTIME
+// KJS_WITH_FULL_RUNTIME
+import kotlin.coroutines.*
+import kotlin.coroutines.intrinsics.*
+
+inline class IC(val s: String)
+
+suspend fun foo(x: String = "OK") = suspendCoroutineUninterceptedOrReturn<IC> {
+    it.resume(IC(x))
+    COROUTINE_SUSPENDED
+}
+
+fun box(): String {
+    var res = ""
+    suspend { res = foo().s }.startCoroutine(Continuation(EmptyCoroutineContext) { it.getOrThrow() })
+    return res
+}