Do not add all modules from module path when compiling unnamed module

Note that javac reports a nice error in this case ("package foo is
declared in module lib, which is not in the module graph"), but we only
report "unresolved reference" because the corresponding modules are not
added to classpath roots. We should improve this in the future

 #KT-18598 In Progress

compiler/testData/javaModules/unnamedDoesNotReadNotAdded/moduleB/usage.kt

@@ -0,0 +1,5 @@
+import foo.Foo
+
+fun usage() {
+    Foo()
+}