Update the go doc for linker flags. Remove flags that no longer
exist. Also remove flags that are intended for debugging the
linker from user docs. Add -aslr to the doc.
The -n flag does nothing except print a nearly useless message on
XCOFF linking. Deprecate it.
Fixes #64476.
Change-Id: I518c9c6cc009eae50b7c11308348524ad6a62b69
Reviewed-on: https://go-review.googlesource.com/c/go/+/546615 Reviewed-by: Than McIntosh <thanm@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>