[BUGFIX] Add default csc-mailform DIV wrap

A new form element does not have any class settings. This issue
reintroduces stdWrap possibilites for the new form system extension.

Change-Id: Id0cff00892f2be0255d639f3bfbb7afe14ef6177
Fixes: #31120
Reviewed-on: http://review.typo3.org/6042
Reviewed-by: Steffen Ritter
Reviewed-by: Xavier Perseguers
Reviewed-by: Georg Ringer
Reviewed-by: Oliver Hader
Tested-by: Oliver Hader