[cairo] [patch] remove warnings and win32 build

[Pierre]

Hello,

These two patches try to improve win32 support in cairo and fix many
warnings and possible compilation errors:

- allow to disable the Win32 surface and still enable the mutex initialisation
- remove uint64 negate macros and implementaion, unused but still a non sense
- fix many compilations warnings (-Wall or on windows) [2]

The only remaining warning is in pixman, fbpict.c, in the
fbCompositeSolidMask_nx8888x8888C function. I'm not sure about the
goal of the gulty line (in the FbInOverC macro), so I left it
untouched:

    __t = (CARD32) (CARD8) (__t | (-(__t >> 8)));

All values being unsigned. Any idea?

I also updated the cairo-win32 archives, a small doc and the downloads
are available on my server [3].

--Pierre

[1] http://blog.thepimp.net/misc/cairowin32/buildlog.txt

[2] http://blog.thepimp.net/misc/cairowin32/pixman_win32_patch.txt
     http://blog.thepimp.net/misc/cairowin32/cairo_win32_patch.txt

[3] http://blog.thepimp.net/misc/cairowin32/