pwm: atmel: Don't use pwm consumer API

Lowlevel driver callbacks are not supposed to use the consumer API
functions. Currently this works, but with the upcoming locking changes
this probably results in dead locks.

Reviewed-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Link: https://lore.kernel.org/r/20240129085627.2386470-2-u.kleine-koenig@pengutronix.de


Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>