kasli: add IRQ

[MorganTL]

ARTIQ Pull Request

Description of Changes

This is part one of WRPLL port to kasli 2.0.

• add asm! to get vmim & vimp CSR
• add IRQ control and enable IRQ on runtime and satellite

Type of Changes

	Type
✓	:sparkles: New feature

Steps (Choose relevant, delete irrelevant before submitting)

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Licensing

See copyright & licensing for more info. ARTIQ files that do not contain a license header are copyrighted by M-Labs Limited and are licensed under LGPLv3+.

[MorganTL]

Force pushed to use asm! to get vmim & vmip CSR instead of importing the whole vexriscv crate.

[sbourdeauducq]

Looks good, will merge before or after release-8 branching depending on the status of the rest of the code that could go into ARTIQ-8.