uboot-phytec

katmai: fix section overlap problem

Since we didn't want to remove features from the configuration, we
decided to increase the U-Boot image size (add one flash sector).

Also changed the default environment definition to make it
independent of such changes.

Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Stefan Roese <sr@denx.de>