rbac.init_can(): do not reassign and thus return path converned permission

breaks permission merge for app modules
i.e.: 'App.supromongod.view.ControlTools' == >> '/supromongod/view/ControlTools'
fix d854d64f0ac64fc8f953e67a71218ead091e61af

Signed-off-by: Oleg Verych <olecom@gmail.com>