mfd: max77686: Remove unused struct max77686_opmode_data

The defined struct max77686_opmode_data isn't used neither by
the max77686 mfd driver nor the drivers for its sub-devices.
Signed-off-by: NJavier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: NChanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: NLee Jones <lee.jones@linaro.org>

include/linux/mfd/max77686.h

@@ -125,9 +125,4 @@ enum max77686_opmode {
 	MAX77686_OPMODE_STANDBY,
 };
 
-struct max77686_opmode_data {
-	int id;
-	int mode;
-};
-
 #endif /* __LINUX_MFD_MAX77686_H */