doc/mksyntaxgo: add Go doc links

Add "go doc" links. See https://go.dev/doc/comment#doclinks

Change-Id: Ie3444af537407a5765edc0c6c777af5779f1259e
Reviewed-on: https://code-review.googlesource.com/c/re2/+/62250
Reviewed-by: Paul Wankadia <junyer@google.com>
Reviewed-by: Alex Chernyakhovsky <achernya@google.com>
1 file changed