staging: greybus: pwm: Rely on pwm framework to pass a valid hwpwm

The pwm framework already asserts to only pass a hwpwm value (= which)
less than npwm (= pwmc->pwm_max + 1). So there is no need to recheck
this condition. Drop the respective checks.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/e003bc5e8e66f27f2b8fdc525a536d865888cffe.1707900770.git.u.kleine-koenig@pengutronix.deSigned-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

drivers/staging/greybus/pwm.c

@@ -46,9 +46,6 @@ static int gb_pwm_activate_operation(struct pwm_chip *chip, u8 which)
 	struct gbphy_device *gbphy_dev;
 	int ret;
 
-	if (which > pwmc->pwm_max)
-		return -EINVAL;
-
 	request.which = which;
 
 	gbphy_dev = to_gbphy_dev(pwmchip_parent(chip));
@@ -71,9 +68,6 @@ static int gb_pwm_deactivate_operation(struct pwm_chip *chip, u8 which)
 	struct gbphy_device *gbphy_dev;
 	int ret;
 
-	if (which > pwmc->pwm_max)
-		return -EINVAL;
-
 	request.which = which;
 
 	gbphy_dev = to_gbphy_dev(pwmchip_parent(chip));
@@ -97,9 +91,6 @@ static int gb_pwm_config_operation(struct pwm_chip *chip,
 	struct gbphy_device *gbphy_dev;
 	int ret;
 
-	if (which > pwmc->pwm_max)
-		return -EINVAL;
-
 	request.which = which;
 	request.duty = cpu_to_le32(duty);
 	request.period = cpu_to_le32(period);
@@ -125,9 +116,6 @@ static int gb_pwm_set_polarity_operation(struct pwm_chip *chip,
 	struct gbphy_device *gbphy_dev;
 	int ret;
 
-	if (which > pwmc->pwm_max)
-		return -EINVAL;
-
 	request.which = which;
 	request.polarity = polarity;
 
@@ -151,9 +139,6 @@ static int gb_pwm_enable_operation(struct pwm_chip *chip, u8 which)
 	struct gbphy_device *gbphy_dev;
 	int ret;
 
-	if (which > pwmc->pwm_max)
-		return -EINVAL;
-
 	request.which = which;
 
 	gbphy_dev = to_gbphy_dev(pwmchip_parent(chip));
@@ -176,9 +161,6 @@ static int gb_pwm_disable_operation(struct pwm_chip *chip, u8 which)
 	struct gbphy_device *gbphy_dev;
 	int ret;
 
-	if (which > pwmc->pwm_max)
-		return -EINVAL;
-
 	request.which = which;
 
 	ret = gb_operation_sync(pwmc->connection, GB_PWM_TYPE_DISABLE,