ASoC: rsnd: set pm_ops in hibernate-compatible way

Use SET_SYSTEM_SLEEP_PM_OPS() macro instead of direct assignment to
.suspend and .resume fields.

This makes driver working after restore from hibernation.

Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Signed-off-by: Mark Brown <broonie@kernel.org>