[mono] Remove w32 subsystem on wasm

[CoffeeFlux]

This runtime code (w32* files) should be largely unnecessary for netcore after #47333 lands, and we should get rid of it as much as possible and make sure it's not present on wasm. If we do use it in a single place, it might be worth some refactoring to put the relevant code elsewhere.

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Issue Details

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This code should be largely unnecessary for netcore after #47333 lands, and we should get rid of it as much as possible and make sure it's not present on wasm.

Author:	CoffeeFlux
Assignees:	-
Labels:	area-VM-meta-mono
Milestone:	6.0.0

[ghost]

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Issue Details

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This runtime code (w32* files) should be largely unnecessary for netcore after #47333 lands, and we should get rid of it as much as possible and make sure it's not present on wasm. If we do use it in a single place, it might be worth some refactoring to put the relevant code elsewhere.

Author:	CoffeeFlux
Assignees:	-
Labels:	arch-wasm, area-VM-meta-mono, size-reduction
Milestone:	6.0.0

[CoffeeFlux]

Some of this is held alive by EventPipe, and that will need to be refactored out. Otherwise, a lot will go away with #47333

[CoffeeFlux]

This is mostly done, so I think we're good here. The remaining bits are either held by EventPipe or Monitor.