pwm: meson: modify and simplify calculation in meson_pwm_get_state

I don't see a reason why we should treat the case lo < hi differently
and return 0 as period and duty_cycle. The current logic was added with
c375bcb ("pwm: meson: Read the full hardware state in
meson_pwm_get_state()"), Martin as original author doesn't remember why
it was implemented this way back then.
So let's handle it as normal use case and also remove the optimization
for lo == 0. I think the improved readability is worth it.

Fixes: c375bcb ("pwm: meson: Read the full hardware state in meson_pwm_get_state()")
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Dmitry Rokosov <ddrokosov@sberdevices.ru>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

drivers/pwm/pwm-meson.c

@@ -351,18 +351,8 @@ static int meson_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
 	channel->lo = FIELD_GET(PWM_LOW_MASK, value);
 	channel->hi = FIELD_GET(PWM_HIGH_MASK, value);
 
-	if (channel->lo == 0) {
-		state->period = meson_pwm_cnt_to_ns(chip, pwm, channel->hi);
-		state->duty_cycle = state->period;
-	} else if (channel->lo >= channel->hi) {
-		state->period = meson_pwm_cnt_to_ns(chip, pwm,
-						    channel->lo + channel->hi);
-		state->duty_cycle = meson_pwm_cnt_to_ns(chip, pwm,
-							channel->hi);
-	} else {
-		state->period = 0;
-		state->duty_cycle = 0;
-	}
+	state->period = meson_pwm_cnt_to_ns(chip, pwm, channel->lo + channel->hi);
+	state->duty_cycle = meson_pwm_cnt_to_ns(chip, pwm, channel->hi);
 
 	state->polarity = PWM_POLARITY_NORMAL;