pull: don't mark values for option "rebase" for translation

"false|true|preserve" are actual values for option "rebase"
of the "git-pull" command and should therefore not be marked
for translation.

Signed-off-by: Ralf Thielow <ralf.thielow@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/pull.c

@@ -112,7 +112,7 @@ static struct option pull_options[] = {
 	/* Options passed to git-merge or git-rebase */
 	OPT_GROUP(N_("Options related to merging")),
 	{ OPTION_CALLBACK, 'r', "rebase", &opt_rebase,
-	  N_("false|true|preserve"),
+	  "false|true|preserve",
 	  N_("incorporate changes by rebasing rather than merging"),
 	  PARSE_OPT_OPTARG, parse_opt_rebase },
 	OPT_PASSTHRU('n', NULL, &opt_diffstat, NULL,