JVM_IR: do not box inline classes in suspend synthetic accessors

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

@@ -0,0 +1,29 @@
+// WITH_RUNTIME
+// WITH_COROUTINES
+
+import helpers.*
+import kotlin.coroutines.*
+import kotlin.coroutines.intrinsics.*
+
+@Suppress("UNSUPPORTED_FEATURE")
+inline class I(val x: Any?)
+
+suspend fun suspendHere(): Unit = suspendCoroutineUninterceptedOrReturn { c ->
+    c.resume(Unit)
+    COROUTINE_SUSPENDED
+}
+
+class C {
+    private suspend fun f(): I {
+        suspendHere()
+        return I("OK")
+    }
+
+    fun g() = suspend { f() }
+}
+
+fun box(): String {
+    var result = "fail"
+    suspend { result = C().g()().x as String }.startCoroutine(EmptyContinuation)
+    return result
+}