KT-17689: Fix TypeAliasQualifier to provide enum entries descriptors

- this adds enum entries to the completion on the typealiases
- we cannot use `unsubstitutedInnerClassesScope` instead of `EnumEntriesScope` because it allows to complete things that are not allowed to be resolved by the Kotlin compiler; see `EnumEntriesScope` doc for details
- ^KT-17689 Fixed

idea/idea-completion/testData/basic/common/EnumItemsThroughChainedTypeAlias.kt

@@ -0,0 +1,14 @@
+enum class A {
+    ONE;
+    class B // Not allowed to resolve through typealiases
+}
+
+typealias AA = A
+typealias AAA = AA
+
+fun usage() {
+    AAA.<caret>
+}
+
+// EXIST: ONE
+// ABSENT: B

idea/idea-completion/testData/basic/common/EnumItemsThroughSingleTypeAlias.kt

@@ -0,0 +1,13 @@
+enum class A {
+    ONE;
+    class B // Not allowed to resolve through typealiases
+}
+
+typealias AA = A
+
+fun usage() {
+    AA.<caret>
+}
+
+// EXIST: ONE, values, valueOf
+// ABSENT: B