env: -u option fails due to typo

The -u option is supposed to be allowed to appear multiple times; the
option string supplied to getopt32long requires it to be followed by a
nonnegative integer.

Reported-by: Keith Maxwell <keith.maxwell@gmail.com>
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

coreutils/env.c

@@ -54,7 +54,7 @@ int env_main(int argc UNUSED_PARAM, char **argv)
 	unsigned opts;
 	llist_t *unset_env = NULL;
 
-	opts = getopt32long(argv, "+iu:+",
+	opts = getopt32long(argv, "+iu:*",
 			"ignore-environment\0" No_argument       "i"
 			"unset\0"              Required_argument "u"
 			, &unset_env