git-clone: honor "--" to end argument parsing

Signed-off-by: Heikki Orsila <heikki.orsila@iki.fi>

Documentation/git-clone.txt

@@ -12,7 +12,7 @@ SYNOPSIS
 'git-clone' [--template=<template_directory>]
 	  [-l] [-s] [--no-hardlinks] [-q] [-n] [--bare]
 	  [-o <name>] [-u <upload-pack>] [--reference <repository>]
-	  [--depth <depth>] <repository> [<directory>]
+	  [--depth <depth>] [--] <repository> [<directory>]
 
 DESCRIPTION
 -----------

git-clone.sh

@@ -14,7 +14,7 @@ die() {
 }
 
 usage() {
-	die "Usage: $0 [--template=<template_directory>] [--reference <reference-repo>] [--bare] [-l [-s]] [-q] [-u <upload-pack>] [--origin <name>] [--depth <n>] [-n] <repo> [<dir>]"
+	die "Usage: $0 [--template=<template_directory>] [--reference <reference-repo>] [--bare] [-l [-s]] [-q] [-u <upload-pack>] [--origin <name>] [--depth <n>] [-n] [--] <repo> [<dir>]"
 }
 
 get_repo_base() {
@@ -160,6 +160,9 @@ while
 	*,--depth)
 		shift
 		depth="--depth=$1";;
+	*,--)
+		shift
+		break ;;
 	*,-*) usage ;;
 	*) break ;;
 	esac