log, format-patch: parsing uses OPT__QUIET

This patch allows users to use the short form -q on
log and format-patch, which was non possible before.

Also the documentation of format-patch mentions -q now.

The documentation of log doesn't even talk about --quiet, so I'll leave
that for more experienced git contributors. ;)
It doesn't seem to change the default behavior, but in combination
with --stat for example it suppresses the actual stats.
however the only relevant code in log is
	if (quiet)
		rev->diffopt.output_format |= DIFF_FORMAT_NO_OUTPUT;

Signed-off-by: Stefan Beller <stefanbeller@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-format-patch.txt

@@ -242,6 +242,7 @@ configuration options in linkgit:git-notes[1] to use this workflow).
 Note that the leading character does not have to be a dot; for example,
 you can use `--suffix=-patch` to get `0001-description-of-my-change-patch`.
 
+-q::
 --quiet::
 	Do not print the names of the generated files to standard output.
 

builtin/log.c

@@ -121,7 +121,7 @@ static void cmd_log_init_finish(int argc, const char **argv, const char *prefix,
 	static struct line_opt_callback_data line_cb = {NULL, NULL, STRING_LIST_INIT_DUP};
 
 	const struct option builtin_log_options[] = {
-		OPT_BOOL(0, "quiet", &quiet, N_("suppress diff output")),
+		OPT__QUIET(&quiet, N_("suppress diff output")),
 		OPT_BOOL(0, "source", &source, N_("show source")),
 		OPT_BOOL(0, "use-mailmap", &mailmap, N_("Use mail map file")),
 		{ OPTION_CALLBACK, 0, "decorate", NULL, NULL, N_("decorate options"),
@@ -1210,8 +1210,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 			    PARSE_OPT_OPTARG, thread_callback },
 		OPT_STRING(0, "signature", &signature, N_("signature"),
 			    N_("add a signature")),
-		OPT_BOOLEAN(0, "quiet", &quiet,
+		OPT__QUIET(&quiet, N_("don't print the patch filenames")),
-			    N_("don't print the patch filenames")),
 		OPT_END()
 	};