pan/midgard: Remove incorrect comment in RA

Ironically, this comment was mistakenly added by the commit that fixed
the purported issue in the comment (1bce7fdecd86 - found by `git blame`)

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4158>
1 file changed