extcon: sm5502: Drop useless include

Don't include <linux/input.h> when the driver does not use anything
from this header file.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Cc: Chanwoo Choi <cw00.choi@samsung.com>
Cc: MyungJoo Ham <myungjoo.ham@samsung.com>