doc txt & -h consistency: correct padding around "[]()"

The whitespace padding of alternatives should be of the form "[-f |
--force]" not "[-f|--force]". Likewise we should not have padding
before the first option, so "(--all | <pack-filename>...)" is correct,
not "( --all | <pack-filename>... )".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
index 50b1a17..c21cfd5 100644
--- a/builtin/commit-graph.c
+++ b/builtin/commit-graph.c
@@ -14,7 +14,7 @@
 
 #define BUILTIN_COMMIT_GRAPH_WRITE_USAGE \
 	N_("git commit-graph write [--object-dir <objdir>] [--append]\n" \
-	   "                       [--split[=<strategy>]] [--reachable|--stdin-packs|--stdin-commits]\n" \
+	   "                       [--split[=<strategy>]] [--reachable | --stdin-packs | --stdin-commits]\n" \
 	   "                       [--changed-paths] [--[no-]max-new-filters <n>] [--[no-]progress]\n" \
 	   "                       <split options>")