board/BuR/*: replace maintainer of BuR boards

Since I'm leaving the company with end of June, the maintainership will
be transferred to Wolfgang Wallner.

Signed-off-by: Hannes Schmelzer <hannes.schmelzer@br-automation.com>
Signed-off-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
4 files changed