mach-ux500: fix ux500 build error

Include ab8500 regulators for DB8500 SoC by default
and fix build issues

Signed-off-by: Sundar Iyer <sundar.iyer@stericsson.com>
[Small fixup for changed boardfiles]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>