dont disable stdout buffering, if setvbuf not available

All MS CRTs, MSVCRT10.DLL and up, export setvbuf. Previously, 1 kernel
write to the console handle, with 1 byte per write, was being done by MS
CRT printf() on a VC build. On other OSes, stdout is usually line buffered
so make the setvbuf in dmake.c's main() a noop if setvbuf isn't available.

extern.h

@@ -176,9 +176,9 @@ char *cygdospath(char *src, int winpath);
 #endif
 #endif
 
-/*  If setvbuf is not available set output to unbuffered */
+/*  If setvbuf is not available, hope the OS has some buffering by default already */
 #if ! HAVE_SETVBUF
-#  define setvbuf(fp,bp,type,len) setbuf(fp,NULL)
+#  define setvbuf(fp,bp,type,len)
 #endif
 
 /* coreleft is used in some debug macros. Only Turbo C seems to provide

win95/microsft/config.h

@@ -100,6 +100,7 @@
 #define HAVE_STRERROR 1
 #define HAVE_TEMPNAM 1
 #define HAVE_FCNTL_H 1
+#define HAVE_SETVBUF 1
 
 /* These defines are needed for itypes.h! (this is tested only with MSVC++ 6.0) */
 #define SIZEOF_INT 4