change "foo.h" to <X11/foo.h> for core headers, e.g. X.h, Xpoll.h;
change "foo.h", "extensions/foo.h" and "X11/foo.h" to
<X11/extensions/foo.h> for extension headers, e.g. Xv.h;
change "foo.[ch]" to <X11/Xtrans/foo.[ch]> for Xtrans files.
Fix link order problems with mingw. Add libdix.a after libmi.a.
Pass -DHAS_FFS to compiler
remove inline code for ffs(). It will link to dix/ffs.c instead added
declaration for ffs()