mlx5en: Add missing media types for 100GBit/s, 200Gbit/s and 400Gbit/s.

Make the mlx5e_mode_table[] array one dimensional, because there is only
one entry, 10G ER/LR, which share the same protocol bit.

This patch only adds support for basic sub-type distinguishing for the
extended protocol bits. Use verbose ifconfig eeprom output to get actual
media type.

Remove write only "connector_type" variable while at it.

Reviewed by: kib
Sponsored by: Mellanox Technologies // NVIDIA Networking

(cherry picked from commit a888087fba37da7c968058062b644f4a79b558c3)