[dev.unified] cmd/compile/internal/types2: remove package height

Same as CL 410342, but for types2.

Updates #51734

Change-Id: I6d6cb8fbb7567d3acf0b8cec0fa74f1344b56a1c
Reviewed-on: https://go-review.googlesource.com/c/go/+/410347


Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@google.com>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>