patchgit-pull: Pass -4/-6 option to git-fetch

> The -4/-6 option should be passed through to git-fetch
> to be consistent with the git-pull man page.
>
> Signed-off-by: Wei Shuyu <wsy@dogben.com>
> ---

>  builtin/pull.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
>
> diff --git a/builtin/pull.c b/builtin/pull.c
> index f7e2c4f2e..166b777ed 100644
> --- a/builtin/pull.c
> +++ b/builtin/pull.c
> @@ -113,6 +113,8 @@ static char *opt_depth;
>  static char *opt_unshallow;
>  static char *opt_update_shallow;
>  static char *opt_refmap;
> +static char *opt_ipv4;
> +static char *opt_ipv6;
>  
>  static struct option pull_options[] = {
>  	/* Shared options */
> @@ -218,6 +220,12 @@ static struct option pull_options[] = {
>  	OPT_PASSTHRU(0, "refmap", &opt_refmap, N_("refmap"),
>  		N_("specify fetch refmap"),
>  		PARSE_OPT_NONEG),
> +	OPT_PASSTHRU('4',  "ipv4", &opt_ipv4, NULL,
> +		N_("use IPv4 addresses only"),
> +		PARSE_OPT_NOARG),
> +	OPT_PASSTHRU('6',  "ipv6", &opt_ipv6, NULL,
> +		N_("use IPv6 addresses only"),
> +		PARSE_OPT_NOARG),
>  
>  	OPT_END()
>  };
> @@ -522,6 +530,10 @@ static int run_fetch(const char *repo, const char **refspecs)
>  		argv_array_push(&args, opt_update_shallow);
>  	if (opt_refmap)
>  		argv_array_push(&args, opt_refmap);
> +	if (opt_ipv4)
> +		argv_array_push(&args, opt_ipv4);
> +	if (opt_ipv6)
> +		argv_array_push(&args, opt_ipv6);
>  
>  	if (repo) {
>  		argv_array_push(&args, repo);