[dev.typeparams] cmd/compile/internal/ir: more position details in dump

When dumping node positions, include column position and the full
inlining tree. These details are helpful for diagnosing "toolstash
-cmp" failures due to subtly changing positions.

Change-Id: I953292d6c01899fd98e2f315bafaa123c4d98ffd
Reviewed-on: https://go-review.googlesource.com/c/go/+/321089


Trust: Matthew Dempsky <mdempsky@google.com>
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Dan Scales <danscales@google.com>