gpio: pmic-eic-sprd: drop unneeded .set() callback

The lines on this chip are input-only. GPIO core can handle the missing
.set() callback so there's no need to implement a dummy here. Drop it.

Reviewed-by: Baolin Wang <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Bartosz Golaszewski <[e-mail]>

drivers/gpio/gpio-pmic-eic-sprd.c

···
 	return 0;
 }
 
-static void sprd_pmic_eic_set(struct gpio_chip *chip, unsigned int offset,
-			      int value)
-{
-	/* EICs are always input, nothing need to do here. */
-}
-
 static int sprd_pmic_eic_set_debounce(struct gpio_chip *chip,
 				      unsigned int offset,
 				      unsigned int debounce)
···
 	pmic_eic->chip.request = sprd_pmic_eic_request;
 	pmic_eic->chip.free = sprd_pmic_eic_free;
 	pmic_eic->chip.set_config = sprd_pmic_eic_set_config;
-	pmic_eic->chip.set = sprd_pmic_eic_set;
 	pmic_eic->chip.get = sprd_pmic_eic_get;
 	pmic_eic->chip.can_sleep = true;