pwm: adp5585: Set OSC_EN bit to 1 when PWM state is enabled

pwm: adp5585: Set OSC_EN bit to 1 when PWM state is enabled

It turns out that OSC_EN bit in GERNERAL_CFG register has to be set to 1
when PWM state is enabled, otherwise PWM signal won't be generated.

Fixes: e9b503879fd2 ("pwm: adp5585: Add Analog Devices ADP5585 support")
Signed-off-by: Liu Ying <victor.liu@nxp.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://lore.kernel.org/r/20240826083337.1835405-1-victor.liu@nxp.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>