Allow use of MSC/CDC USB endpoints for bulk on sam3u2

[9names]

The sam3u2 USB peripheral does not have enough endpoints after CDC and MSC are enabled to enable the BULK endpoints. Bulk endpoints are required for CMSIS-DAP v2 support - the existing projects for this HIC use HID+MSC+CDC

This PR makes it possible for the sam3u2 to enable BULK if either CDC or MSC are disabled.
In order to demonstrate this setup, the sam3u2c_bulk_test_if project has been added which uses HID+CDC+BULK,

I have tested this configuration with a nanoDAP-hs, probe-rs-cli and few computers I had at my disposal:
raspberry pi 4 - hid: 90KB/s, bulk: 152KB/s
AMD 7700x, ubuntu 22.10 - hid: 17KB/s, bulk: 280KB/s
intel u5200, windows 10 - hid: 100KB/s, bulk: 160KB/s

Not sure why my AMD box is so slow with HID, but the speed-up is very significant in this case.

[9names]

Would it make more sense to move usb-msc out of bl and if, and have it added by default to each HIC where it currently exists (except for sam3u2)?
The HICs already add usb-bulk and usb-hid themselves, so it would seem reasonable to include usb-msc there as well.

[mbrossard]

The additive nature of DAPLink's build configuration is problematic for interface that have limited amount of endpoints. I did also consider your idea of splitting further the configuration of bl / if projects, but I got worried it would grow the verbosity of the projects.yaml. Instead I am leaning towards adding the option to disable functionality from the default interface configuration. I ported some of the changes I had started to make onto the feature/flexible-usb-configuration branch and modified sam3u2c_if to disable MSC endpoint and replace HID with BULK. I am not 100% sure about modifying sam3u2c_if rather than adding a new project, but this is what I am leaning towards.

I would have usually preferred to go with your change to usb_config.c (which is nicely compact). But in this case where things are a little bit complicated (I don't understand how things work with USBD_HID_EP_INTOUT being set to 0), I would rather be very explicit on the endpoint assignments.

[9names]

Your version looks better to me :)

I opted out of modifying existing projects or removing HID because I was worried existing users might expect everything to stay the same, but I assume you know your users better than I do.
Turning off HID when BULK is enabled is something I would have done if it were as simple as it is for your branch.

If this were a pure cmake project, I would have made these things selectable at configure time and overridable at build time, but I don't know pygen well enough to know what is possible and what is considered idiomatic usage

[mathias-arm]

Replaced by #1041