mfd: max8997: Use "IS_ENABLED(CONFIG_OF)" for DT code.
mfd: max8997: Use "IS_ENABLED(CONFIG_OF)" for DT code.

Instead of "#if define CONFIG_OF" use "IS_ENABLED(CONFIG_OF)"
option for DT code to avoid if-deffery in code.

Signed-off-by: Manish Badarkhe <227975c36604f4edcba69fb2c44a00e46ac90635@gmail.com>
Signed-off-by: Lee Jones <630e34333487a351a857f6b705e04d30b37c1629@linaro.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs