Add QNX' QNET protocol

no ethertype 0x8203-0x8205 support in trunk.
0x8204 is QNX OS VER 6's qnet ethernet protocol number.

Bug:3934
Change-Id: I5f3e910876bb7fb86de2111f856d026fdf220917
Reviewed-on: https://code.wireshark.org/review/2954
Petri-Dish: Michael Mann <mmann78@netscape.net>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Michael Mann <mmann78@netscape.net>