cmd/compile: consistently use typekind when reporting invalid operation

cmd/compile: consistently use typekind when reporting invalid operation

While at it, make "typekind" awares of "types.Ideal*" types.

Passes toolstash-check.

Change-Id: I092fa8c57ab6b8d9ba0f25d8e1ea44fba48675e5
Reviewed-on: https://go-review.googlesource.com/c/go/+/256438
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>