Action RFC818: merge cortex teams into new arm team

[adamgreig]

No description provided.

[martinmortsell]

Should this email still be cortex-m?

[adamgreig]

New emails aren't set up yet and will take a bit longer to arrange, so I wanted to get the main README updated first.

[jonathanpallant]

This will withdraw my push access to the cortex-ar and arm-dcc repos (which was special-cased but shouldn't continue). I volunteer to join the new Arm team. Can you tack that onto this PR or that does need a different PR?

[jamesmunns]

Just noting that we should update the https://github.com/rust-lang/team repo in parallel with this to represent the new structure.

[adamgreig]

This will withdraw my push access to the cortex-ar and arm-dcc repos (which was special-cased but shouldn't continue). I volunteer to join the new Arm team. Can you tack that onto this PR or that does need a different PR?

Thank you! Please could you make a separate PR for that so the new team can vote as normal?

[jonathanpallant]

This will withdraw my push access to the cortex-ar and arm-dcc repos (which was special-cased but shouldn't continue). I volunteer to join the new Arm team. Can you tack that onto this PR or that does need a different PR?

Thank you! Please could you make a separate PR for that so the new team can vote as normal?

#824