send-email: --smtp-ssl-cert-path takes an argument

35035bb (send-email: be explicit with SSL certificate verification,
2013-07-18) forgot to specify that --smtp-ssl-cert-path takes a string
argument.  This means that the option could not actually be used as
intended.  Presumably noone noticed because it's much easier to set it
through configs anyway.

Add the required "=s".

Signed-off-by: Thomas Rast <tr@thomasrast.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-send-email.perl

@@ -291,7 +291,7 @@ my $rc = GetOptions("h" => \$help,
 		    "smtp-pass:s" => \$smtp_authpass,
 		    "smtp-ssl" => sub { $smtp_encryption = 'ssl' },
 		    "smtp-encryption=s" => \$smtp_encryption,
-		    "smtp-ssl-cert-path" => \$smtp_ssl_cert_path,
+		    "smtp-ssl-cert-path=s" => \$smtp_ssl_cert_path,
 		    "smtp-debug:i" => \$debug_net_smtp,
 		    "smtp-domain:s" => \$smtp_domain,
 		    "identity=s" => \$identity,