leds: pca9532: Use PWM1 for hardware blinking

leds: pca9532: Use PWM1 for hardware blinking

PSC0/PWM0 are used by all LEDs for brightness and blinking. This causes
conflicts when you set a brightness of a new LED while an other one is
already using PWM0 for blinking.

Use PSC1/PWM1 for blinking.
Check that no other LED is already blinking with a different PSC1/PWM1
configuration to avoid conflict.

Signed-off-by: Bastien Curutchet <bastien.curutchet@bootlin.com>
Link: https://lore.kernel.org/r/20240617143910.154546-3-bastien.curutchet@bootlin.com
Signed-off-by: Lee Jones <lee@kernel.org>