Unify gdb printf functions

Now that filtered and unfiltered output can be treated identically, we
can unify the printf family of functions.  This is done under the name
"gdb_printf".  Most of this patch was written by script.

gdb/exceptions.c

@@ -88,7 +88,7 @@ print_exception (struct ui_file *file, const struct gdb_exception &e)
 	  file->write (start, end - start);
 	}
     }					    
-  fprintf_filtered (file, "\n");
+  gdb_printf (file, "\n");
 
   /* Now append the annotation.  */
   switch (e.reason)