Broken auto-clonetype on Scala 2.11.12 (#1480)

* Added broken auto-clonetype test

* Added bugfix for 2.11

* Add descriptive comment for 2.11 special case

* Update src/test/scala/chiselTests/AutoClonetypeSpec.scala

* Update src/test/scala/chiselTests/AutoClonetypeSpec.scala

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>