ASoC: tegra186_asrc: mark runtime-pm functions as __maybe_unused

ASoC: tegra186_asrc: mark runtime-pm functions as __maybe_unused

sound/soc/tegra/tegra186_asrc.c:90:12: error: ‘tegra186_asrc_runtime_resume’ defined but not used [-Werror=unused-function]
 static int tegra186_asrc_runtime_resume(struct device *dev)
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
sound/soc/tegra/tegra186_asrc.c:80:12: error: ‘tegra186_asrc_runtime_suspend’ defined but not used [-Werror=unused-function]
 static int tegra186_asrc_runtime_suspend(struct device *dev)
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Mark these functions as __maybe_unused to avoid this kind of warning.

Fixes: a2df8c2d5b36 ("ASoC: tegra: Add Tegra186 based ASRC driver")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Sameer Pujar <spujar@nvidia.com>
Link: https://lore.kernel.org/r/20220411020908.580-1-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>