jvm-abi-gen: Remove effectively private classes from ABI

#KT-64590 Fixed

plugins/jvm-abi-gen/testData/compile/multifileClassOptimizedWithRemovePrivateOption/app/app.kt

@@ -0,0 +1,12 @@
+package app
+
+import lib.*
+
+fun runAppAndReturnOk(): String {
+    f1()
+    if (v1 != "OK") return "Fail 1"
+    f2()
+    if (v2 != "OK") return "Fail 2"
+
+    return "OK"
+}

plugins/jvm-abi-gen/testData/compile/multifileClassOptimizedWithRemovePrivateOption/directives.txt

@@ -0,0 +1,2 @@
+// INHERIT_MULTIFILE_PARTS
+// REMOVE_PRIVATE_CLASSES

plugins/jvm-abi-gen/testData/compile/multifileClassOptimizedWithRemovePrivateOption/lib/part1.kt

@@ -0,0 +1,7 @@
+@file:JvmMultifileClass
+@file:JvmName("Multifile")
+package lib
+
+typealias T1 = String
+fun f1() {}
+val v1: T1 = "OK"

plugins/jvm-abi-gen/testData/compile/multifileClassOptimizedWithRemovePrivateOption/lib/part2.kt

@@ -0,0 +1,7 @@
+@file:JvmMultifileClass
+@file:JvmName("Multifile")
+package lib
+
+typealias T2 = String
+fun f2() {}
+val v2: T2 = "OK"