rogue4: don't try to close the scorefile if it isn't open.

The MSVC library uses a debug assertion to prevent closing file
descriptors that are negative.  This is always the case with the
scoreboard file descriptor if the scoreboard has been compiled out.

rogue4/save.c

@@ -160,7 +160,10 @@ register FILE *savef;
     /*
      * close any open score file
      */
-    close(fd);
+    if (fd >= 0) {
+        close(fd);
+        fd = -1;
+    }
     move(LINES-1, 0);
     refresh();
     fstat(md_fileno(savef), &sbuf);