nxp_enet: RT11xx enet1g support

[jman168]

Is your enhancement proposal related to a problem? Please describe.
Currently there is no support for the 1G enet peripheral present on the RT11xx series of micro controllers.

Describe the solution you'd like
I think the new nxp_enet driver would be a great point of entry to add support for this peripheral.

Describe alternatives you've considered
There aren't really any alternatives to this besides just not having support for it.

Additional context
I am currently on an FSAE team (student design team that designs, builds, and competes with formula style race cars, shout out Gator Motorsports and the University of Florida!) and we are developing our system around gigabit automotive Ethernet and the RT1176. I played around with the new driver and managed to get gigabit to work in a very crippled state (PHY is only working in very specific circumstances as it doesn't have a driver, auto negotiation doesn't work, etc...). If you're interested in taking a look it's here https://github.com/Gator-Motorsports/zephyr/tree/rt1170_eth (don't judge, I know it's very crude, I just wanted a proof of concept before we went and committed to 1G, plus we don't care about auto negotiation so this is perfectly usable for us).

I really would like to see official support for this as this is one of the biggest features not supported on the RT11xx platform as of now. We are happy to help in any way the community needs, as we will be working very heavily with the platform for the next six months or so at least, we will get a lot of testing and development time we'd like the Zephyr community to benefit from as much as possible, whether that be in the form of issues, code, testing, etc...