cl_main.c:
added #include "winquake.h" back in, since ming and msvc
wouldn't build without it
qw_client.dsp and makefile.mgw:
added vid_win.c
(need to rename qw_*.dsp to qf_*.dsp one of these days...)
Preferred method will be using autoconf & automake with ./configure
but that requires single-hosting Mingw which is bit complicated. You can
also use CYGWIN to compile.