ASoC: codecs: rk3308: fix build warning without OF

Merge series from Luca Ceresoli <luca.ceresoli@bootlin.com>:

This small series fixes a build warning reported by kernel test robot
<lkp@intel.com> and improves the Kconfig entry.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
---
Changes in v2:
- Replaced v1 implementation with __maybe_unused
- Added patch to depend on || COMPILE_TEST
- Link to v1: https://lore.kernel.org/r/20240329-rk3308-audio-codec-fix-warning-v1-1-b9d177fcd6c9@bootlin.com

---
Luca Ceresoli (2):
      ASoC: codecs: rk3308: fix "defined but not used" warning on !OF
      ASoC: codecs: rk3308: depend on ARM64 || COMPILE_TEST

 sound/soc/codecs/Kconfig        | 1 +
 sound/soc/codecs/rk3308_codec.c | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)
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base-commit: 4ed0915f5bc4bcc81bca783a5b984f3d81e9764e
change-id: 20240329-rk3308-audio-codec-fix-warning-51bb572ebd96

Best regards,
--
Luca Ceresoli <luca.ceresoli@bootlin.com>