Merge branch 'jk/parseopt-usage-msg-opt'

The function usage_msg_opt() has been updated to say "fatal:"
before the custom message programs give, when they want to die
with a message about wrong command line options followed by the
standard usage string.

* jk/parseopt-usage-msg-opt:
  parse-options: print "fatal:" before usage_msg_opt()

parse-options.c

@@ -661,7 +661,7 @@ void NORETURN usage_msg_opt(const char *msg,
 		   const char * const *usagestr,
 		   const struct option *options)
 {
-	fprintf(stderr, "%s\n\n", msg);
+	fprintf(stderr, "fatal: %s\n\n", msg);
 	usage_with_options(usagestr, options);
 }