USB: CDC-ACM enhacements

[tore-espressif]

Change description

Change log

• New function cdc_acm_host_register_new_dev_callback. This allows you to get New Device notifications even if you use the default driver, or you didn't install the driver yourself
• Receive buffer has configurable size. This is useful if you expect data transfers larger then Maximum Packet Size.
• Receive buffer has 'append' function. In the Data Received callback you can signal that you wait for more data and the current data were not yet processed. In this case, the CDC driver appends new data to the already received data. This is especially useful if the upper layer messages consist of multiple USB transfers and you don't want to waste more RAM and CPU copying the data around.

Breaking change

The last point^ is unfortunately a breaking change. Some cellular modems in esp_modem need it.

Additional info

• Test and README extended
• There are changes in other USB components too -> the CI needs all components compatible with latest version of CDC-ACM. These components will be properly updated and release in subsequent PR

[github-actions[bot]]

Unit Test Results

  11 files  ±0    11 suites  ±0   14m 44s :stopwatch: +5s   16 tests ±0    16 :heavy_check_mark: ±0  0 :zzz: ±0  0 :x: ±0  162 runs  ±0  162 :heavy_check_mark: ±0  0 :zzz: ±0  0 :x: ±0 

Results for commit 99ae92be. ± Comparison against base commit a66d5e52.

:recycle: This comment has been updated with latest results.

[tore-espressif]

@roma-jam @esp-saurabhbansal PTAL! @Dazza0 Could you please check the part where I'm modifying the 'const data_buffer' in usb_transfer_t? It is a very handy feature to have zero-copy receive (IN) path

cc @david-cermak

[Dazza0]

@tore-espressif Whoops, my bad (didn't review it in time). W.r.t to modifying the const buffer, IMO it should be OK for now. But the cleaner solution would be to support that officially via the USB Host interface (see IDF-6932), so we might need to update the CDC driver again once that is supported.

[tore-espressif]

@Dazza0 no problem. I was impatient and decided to take the odds and live with the consequences :D I can yank the version if it causes problems