JVM IR: Fix generation of parameterless default constructor

The JVM backend does not generate parameterless default constructors for
private constructors and constructors of local, inner, or inline
classes.

compiler/testData/codegen/bytecodeText/constructors/enumPrimaryDefaults.kt

@@ -0,0 +1,15 @@
+enum class Enum(val x: Int = 0) {
+    A,
+    B(0) { override fun f() {} };
+    open fun f() {}
+}
+
+// @Enum.class:
+// 0 <init>\(\)V
+// 1 private <init>\(Ljava/lang/String;II\)V
+// 1 synthetic <init>\(Ljava/lang/String;IIILkotlin/jvm/internal/DefaultConstructorMarker;\)V
+// 1 public synthetic <init>\(Ljava/lang/String;IILkotlin/jvm/internal/DefaultConstructorMarker;\)V
+
+// @Enum$B.class:
+// 0 <init>\(\)V
+// 1 <init>\(Ljava/lang/String;I\)V