Perforce: Fix openSupportMode method for new syntax

Change-Id: I829905cf13a16364739c2a145f755a81bd1c53bf
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>
SVN: Remove dead static function

Change-Id: I5a3b47e3ca1372c1875ce79d20be60d388145e2f
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>