Add hal_features parameter to Adapter::request_device().

[JMS55]

Is your feature request related to a problem? Please describe.
I would like to enable specific Vulkan extensions, that don't (and probably shouldn't) have corresponding wgpu features.

Describe the solution you'd like
Add a hal_features: &[&CStr] parameter to Adapter::request_device().

Describe alternatives you've considered
Currently you can make the device yourself using Adapter::device_from_raw() and Adapter::create_device_from_hal(), but this is a lot of unnecessary boilerplate and duplicate code that needs to be kept up-to-date with wgpu's internals.

[teoxoy]

Which Vulkan extensions are you interested in enabling?

[JMS55]

I need whatever the list of extensions DLSS returns. Currently, on my system, that seems to be:

VK_NVX_binary_import
VK_NVX_image_view_handle
VK_EXT_buffer_device_address
VK_KHR_push_descriptor

[teoxoy]

I see, it's a bit unfortunate that there doesn't seem to be a nice way to implement those on top of our current API.

There has been some talk recently in the group about an upscaling API. The next step is an investigation to see where the middle-ground of DLSS/FSR/MetalFX/XeSS is and how the API could look. There doesn't seem to be an issue opened for this but if you are interested in this being available on the web, I'd encourage you to file one and contribute your findings.

[cwfitzgerald]

#4067 is what will also get you this.