firmware/memmap fixes

[Bernhard Walle]

This patch fixes the problems Andrew encountered in his review and also fixes a
boot problem on i386 in linux-next. That was not present while testing the
patch in tip tree.

However, I don't know how to merge that patches properly. Directly to
linux-next or via -mm? Or via x86?

The patches are against linux-next tree and were tested on i386.


Signed-off-by: Bernhard Walle <bwalle at suse.de>