ABL w. Inductive sensor. Ignore z endstop

Hello Guys,

i am trying to install an inductive Z-endstop on my printer, for Auto bed levelling.
However, i can't find the option to ignore Z-endstops? - The guide i followed (Thomas Salander) uses the #define ENDSTOPS_ONLY_FOR_HOMING however, my firmware (marlin) doesn't have that option????
How do i enable this feature?

Oh and i forgot to mention that i had ABL running with a normal micro Switch.

Nobody have any ideas?

#define ENDSTOPS_ONLY_FOR_HOMING option can be found under configuration_adv.h tab directly under the mechanical settings