doc: fix the bnf like style of some commands

In command line options, variables are entered between < and >

Signed-off-by: Jean-Noël Avila <jn.avila@free.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-init.txt

diff --git a/Documentation/git-init.txt b/Documentation/git-init.txt
index f35f70f..59ecda6 100644
--- a/Documentation/git-init.txt
+++ b/Documentation/git-init.txt
@@ -70,7 +70,7 @@
 +
 If this is reinitialization, the repository will be moved to the specified path.
 
--b <branch-name::
+-b <branch-name>::
 --initial-branch=<branch-name>::
 
 Use the specified name for the initial branch in the newly created repository.

builtin/submodule--helper.c

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index de5ad73..c30896c 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -1308,7 +1308,7 @@ static int module_summary(int argc, const char **argv, const char *prefix)
 	};
 
 	const char *const git_submodule_helper_usage[] = {
-		N_("git submodule--helper summary [<options>] [commit] [--] [<path>]"),
+		N_("git submodule--helper summary [<options>] [<commit>] [--] [<path>]"),
 		NULL
 	};