[ros] remove /base_image addition from camera frame_id

I couldn't find any mention of a /base_image postfix to the frame_id of a ROS Image message anywhere, neither can I think of a reason why that would make sense.

Removal of this hardcoded postfix allows to properly set the frame_id of a video camera from the builder script. If someone really needs the '/base_image' addition, it can still be set from the script.