[RFC,resend] framebuffer rotation patch

[Michal Suchanek]

Hello,

this is a framebuffer rotation patch rebased on top of current trunk.
Between the trunk commits and the actual rotation there are a few
fixes from my local branch most of which can be separated but the
scroll fix conflicts with the rotation patch.

This works for me (including terminal scrolling) in qemu and I
compile-tested earlier version for efi as well. Only videotest and
gfxterm was tested.

Most of the suggestions I got in the previous discussion are
incorporated in the new patch.

The rotation constants are declared as enum but the enum type is not
used because it would cause cyclic dependency between struct mode_info
in video.h and the transform enum in fbtrant.h

Thanks

Michal

fbrot.send.txt
Description: Text document