* winsup.h: Eliminate inclusion of most of the cygwin .h files. Use .h files

only in sources which require them.
* Makefile.in: Generate dependencies with -MD option.

winsup/cygwin/fhandler_raw.cc

@@ -17,6 +17,8 @@
 #include <cygwin/rdevio.h>
 #include <sys/mtio.h>
 #include "cygerrno.h"
+#include "fhandler.h"
+#include "path.h"
 
 /* static wrapper functions to hide the effect of media changes and
    bus resets which occurs after a new media is inserted. This is