thermal/drivers/imx: Remove __maybe_unused notations

thermal/drivers/imx: Remove __maybe_unused notations

Replace SET_RUNTIME_PM_OPS()/SET SYSTEM_SLEEP_PM_OPS() with their modern
RUNTIME_PM_OPS() and SYSTEM_SLEEP_PM_OPS() alternatives.

The combined usage of pm_ptr() and RUNTIME_PM_OPS/SYSTEM_SLEEP_PM_OPS()
allows the compiler to evaluate if the runtime suspend/resume() functions
are used at build time or are simply dead code.

This allows removing __maybe_unused notations from the suspend/resume()
functions.

Signed-off-by: Fabio Estevam <festevam@denx.de>
Link: https://lore.kernel.org/r/20240820012616.1449210-2-festevam@gmail.com
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>