cmd/link: add producer section to wasm binaries

This change adds an optional "producer" section that reports the source
language and compiler version. See
https://github.com/WebAssembly/tool-conventions/blob/master/ProducersSection.md.

It also removes the now redundant "go.version" section.

Fixes #33295.

Change-Id: Ib4c80528728caf9e524fbd3f26822cbbc8b05a75
Reviewed-on: https://go-review.googlesource.com/c/go/+/196804


Run-TryBot: Richard Musiol <neelance@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Agniva De Sarker <agniva.quicksilver@gmail.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>