Fix sunxi compiler warnings

Fixes two sunxi related compiler warnings

Signed-off-by: Oliver Schinagl <oliver@schinagl.nl>
Fix u-boot sunxi-current headers

Currently, there's two problems with the headers and includes.
  * Linux prefers headers to be in alphabetical order, we try to comply
    with this as much as possible, except that:
    - common.h is always first
    - 'normal' headers
    - asm headers
    - asm/arch headers
  * Some headers do not include the headers they need and thus result in
    compile errors mostly when removing 'common.h' as the first header

This patch fixes both issues for sunxi parts only.

Signed-off-by: Oliver Schinagl <oliver@schinagl.nl>
sunxi watchdog: Correct watchdog_set. Was reading garbage from stack/register