staging: greybus: pwm: Drop unused gb_connection_set_data()

The driver never calls gb_connection_get_data(). If there was another
caller (say the greybus core) it cannot use the value because the type
of pwmc (= struct gb_pwm_chip) is only defined in the pwm driver.

So drop the call to gb_connection_set_data().
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/bd2759c325c295f3d9f990609d97eb83a8ca88b8.1707900770.git.u.kleine-koenig@pengutronix.deSigned-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

drivers/staging/greybus/pwm.c

@@ -260,7 +260,6 @@ static int gb_pwm_probe(struct gbphy_device *gbphy_dev,
 	}
 
 	pwmc->connection = connection;
-	gb_connection_set_data(connection, pwmc);
 	gb_gbphy_set_data(gbphy_dev, chip);
 
 	ret = gb_connection_enable(connection);