commit ddf744deee ("drivers: pwm_nrfx: Use Device Tree label as
instance name") removed the config setting for PWM names and replaced
it with DT_NORDIC_NRF_PWM_PWM_*_LABEL.
This change is causing the blink_led and fade_led samples to break
when compiled for nRF52 boards.
Let's update the samples to use the DT setting.
Signed-off-by: Michael Scott <mike@foundries.io>
d318da1db9