[llvm] [docs] Update docs on code-review process (PR #111735)

[Jakub Kuderski via llvm-commits]

================
@@ -150,14 +150,21 @@ almost always associated with a message containing the text "LGTM" (which
 stands for Looks Good To Me). Only approval from a single reviewer is required.
 
 When providing an unqualified LGTM (approval to commit), it is the
-responsibility of the reviewer to have reviewed all of the discussion and
+responsibility of the reviewer to have reviewed all of the prior discussion and
 feedback from all reviewers ensuring that all feedback has been addressed and
 that all other reviewers will almost surely be satisfied with the patch being
 approved. If unsure, the reviewer should provide a qualified approval, (e.g.,
 "LGTM, but please wait for @someone, @someone_else"). You may also do this if
 you are fairly certain that a particular community member will wish to review,
 even if that person hasn't done so yet.
 
+If new comments are posted after the patch has been approved (but not yet
+merged), these need to be addressed following similar process as outlined
+above. Specifically, a reviewer should confirm that all feedback has been
+addressed before a patch is merged, including the newly posted comments.
+Exceptions apply - e.g. there's no need to confirm that a comment requesting a
----------------
kuhar wrote:

To follow the style above

```suggestion
Exceptions apply, e.g., there's no need to confirm that a comment requesting a
```

https://github.com/llvm/llvm-project/pull/111735