samples: usb: audio: Samples for usb audio fail building

[PerMac]

Describe the bug
Samples from /zephyr/samples/subsys/usb/audio fail during building.

To Reproduce
Steps to reproduce the behavior:

1. go to your zephyr dir
2. run: ./scripts/twister -T samples/subsys/usb/audio/ -p nrf52840dk_nrf52840 -v -v --inline-logs
3. See error

Expected behavior
The build works

Impact
showstopper

Logs and console output
Part of the logs

/home/maciej/zephyrproject2/zephyr/subsys/usb/class/audio/audio.c:978:1: note: in expansion of macro 'UTIL_LISTIFY'
  978 | UTIL_LISTIFY(HEADSET_DEVICE_COUNT, HEADSET_DEVICE, HS)
      | ^~~~~~~~~~~~
/home/maciej/zephyrproject2/zephyr/include/net/buf.h:1114:63: error: expected ';', ',' or ')' before '=' token
 1114 |  static const struct net_buf_pool_fixed net_buf_fixed_##_name = {      \
      |                                                               ^
/home/maciej/zephyrproject2/zephyr/subsys/usb/class/audio/audio.c:947:2: note: in expansion of macro 'NET_BUF_POOL_FIXED_DEFINE'
  947 |  NET_BUF_POOL_FIXED_DEFINE(name, 5, size, net_buf_destroy)
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~
/home/maciej/zephyrproject2/zephyr/subsys/usb/class/audio/audio.c:969:2: note: in expansion of macro 'DEFINE_BUF_POOL'
  969 |  DEFINE_BUF_POOL(audio_data_pool_hs_##i, EP_SIZE(dev##_HP, i)); \
      |  ^~~~~~~~~~~~~~~
/home/maciej/zephyrproject2/zephyr/include/sys/util_loops.h:1086:2: note: in expansion of macro 'HEADSET_DEVICE'
 1086 |  F(0, __VA_ARGS__)
      |  ^
/home/maciej/zephyrproject2/zephyr/include/sys/util_internal.h:85:36: note: in expansion of macro 'Z_UTIL_LISTIFY_1'
   85 | #define UTIL_PRIMITIVE_CAT(a, ...) a##__VA_ARGS__
      |                                    ^
/home/maciej/zephyrproject2/zephyr/subsys/usb/class/audio/audio.c:978:1: note: in expansion of macro 'UTIL_LISTIFY'
  978 | UTIL_LISTIFY(HEADSET_DEVICE_COUNT, HEADSET_DEVICE, HS)
      | ^~~~~~~~~~~~
/home/maciej/zephyrproject2/zephyr/subsys/usb/class/audio/audio.c:847:13: error: 'audio_receive_cb' defined but not used [-Werror=unused-function]
  847 | static void audio_receive_cb(uint8_t ep, enum usb_dc_ep_cb_status_code status)
      |             ^~~~~~~~~~~~~~~~
/home/maciej/zephyrproject2/zephyr/subsys/usb/class/audio/audio.c:777:12: error: 'usb_audio_device_init' defined but not used [-Werror=unused-function]
  777 | static int usb_audio_device_init(const struct device *dev)
      |            ^~~~~~~~~~~~~~~~~~~~~
/home/maciej/zephyrproject2/zephyr/subsys/usb/class/audio/audio.c:761:12: error: 'audio_class_handle_req' defined but not used [-Werror=unused-function]
  761 | static int audio_class_handle_req(struct usb_setup_packet *pSetup,
      |            ^~~~~~~~~~~~~~~~~~~~~~
/home/maciej/zephyrproject2/zephyr/subsys/usb/class/audio/audio.c:682:12: error: 'audio_custom_handler' defined but not used [-Werror=unused-function]
  682 | static int audio_custom_handler(struct usb_setup_packet *pSetup, int32_t *len,
      |            ^~~~~~~~~~~~~~~~~~~~
/home/maciej/zephyrproject2/zephyr/subsys/usb/class/audio/audio.c:331:13: error: 'audio_cb_usb_status' defined but not used [-Werror=unused-function]
  331 | static void audio_cb_usb_status(struct usb_cfg_data *cfg,
      |             ^~~~~~~~~~~~~~~~~~~
/home/maciej/zephyrproject2/zephyr/subsys/usb/class/audio/audio.c:287:13: error: 'audio_interface_config' defined but not used [-Werror=unused-function]
  287 | static void audio_interface_config(struct usb_desc_header *head,
      |             ^~~~~~~~~~~~~~~~~~~~~~

Environment (please complete the following information):

• OS: Ubuntu 18.04
• Toolchain Zephyr SDK
• Commit SHA or Version used: zephyr-v2.5.0-449-g31c1dc58ad90

Additional context
Add any other context about the problem here.

[jfischer-no]

introduced by de84575

[mbolivar-nordic]

introduced by de84575

This is breaking CI for unrelated PRs; I'm sending a revert