Default themes: Don't use /** docblocks for simple multiline comments.

props DrewAPicture, ericlewis.
fixes #25256.

Built from https://develop.svn.wordpress.org/trunk@25746


git-svn-id: http://core.svn.wordpress.org/trunk@25659 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Hook documentation for wp-admin/admin.php.

props DrewAPicture for initial patch.
fixes #25442.

Built from https://develop.svn.wordpress.org/trunk@25747


git-svn-id: http://core.svn.wordpress.org/trunk@25660 1a063a9b-81f0-0310-95a4-ce76da25c4cd