cmd: parse the port of an eee command from the start of the word

parse_eee() sniffs word 2 for a trailing 'g' or 'm' to tell a speed from
a port number, and advances idx past the digits to do so. The port branch
then hands that advanced idx to cmd_parse_port_separator(), which expects
the first character of the number and finds the separator instead, so it
returns 0 and the command is rejected. Every other caller passes
cmd_words_b[].

The result is that no eee command carrying a port number works, in any
argument order, and the stored per-port lines a saved configuration
replays are silently dropped.

Reported by tofurky in issue #459, along with this fix.

cmd_parser.c

@@ -1419,7 +1419,7 @@ void parse_eee(void)
 			speed_word = 2;
 		} else if (cmd_is_space_or_nul(idx)) {
 			// Word 2 is a port number
-			if (cmd_parse_port_separator(idx) == 0) {
+			if (cmd_parse_port_separator(cmd_words_b[2]) == 0) {
 				cmd_error("Speed word invalid, use: [100m|1g|2g5]\n");
 				return;
 			}