brcm63xx: tag images/dtbs with profiles

This prevents generating every supported image, except for de "Default" profile.
Also fixes Neufbox 6 image generation.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Signed-off-by: Jonas Gorski <jogo@openwrt.org>

SVN-Revision: 42210