docs: add accidentally dropped "at"

When rewriting 20c56e18c21 after review, I accidentally dropped the "at"
here. Sorry for that, and let's fix it up!

Signed-off-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Fixes: 20c56e18c21 ("docs: use proper links instead of code-tags")
Reviewed-by: Eric Engestrom <eric.engestrom@intel.com>
1 file changed