Support CoreMgmt over DRTIO

[occheung]

ARTIQ Pull Request

Description of Changes

This PR implements the followings:

1. Flashing gateware/bootloader/firmware through artiq_coremgmt via config write similar to Zynq device.
2. Implement corresponding core-mgmt handling for satellites
3. Create new DRTIO messages for (2).

Item (1) should belong to its own PR, but I am not sure if we should toe Zynq's line on this. Coremgmt now requires a DRTIO destination byte. It is currently implemented as mandatory, so it is a breaking change.

Related Issue

Closes #2498

Known Issues

• Satellite will be unable to respond to AUX traffic while flashing. Taking down DRTIO link and reboot is WIP. We may want to rethink the new DRTIO messages for this.
• Routing the new reply messages are probably missing.

Tests

Remote flashing, rebooting, logging (via artiq_coremgmt and aqctl_corelog), and configuration via DRTIO between 2 core devices. Core devices ranges from Kasli 1.1, 2.0 and Kasli-SoC.

A corresponding PR will be opened to artiq-zynq soon.

Type of Changes

	Type
✓	:sparkles: New feature

Steps (Choose relevant, delete irrelevant before submitting)

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Licensing

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