cmd/compile, cmd/link: doc: docs are incomplete

[ainar-g]

The documentation for those commands on the website (compile, link) lacks certain flags. For example, compile's page is missing the very useful -m flag, and link's page -- -a, -buildid, and others.

(Ideally, those sections would be generated from go tool (compile|link) -h output, but I don't know enough details to propose a full solution.)

[ianlancetaylor]

I don't think we should generate the docs from the -h output. The docs and the -h output serve two different purposes.

[hellozee]

I would love to take a shot on it, but first I need to what things I need to add? would just adding the missing flags, do the task?

[gopherbot]

Change https://golang.org/cl/138757 mentions this issue: cmd: add document for some missing flags in cmd/compile and cmd/link