Your system may require changes to extstgmot.c. After making any changes you will need to recompile. Here are some of the options from the source code.
/* Uncomment any of the following declarations to inhibit
the use of home switches or index pulses when homing, or to
ignore limit switches if you don't have them. */
/* Uncomment NO_HOME_SWITCH if you want homing sequence to
ignore the home switch, and only use the index pulse for homing.
This has the effect of making the home switches always appear tripped. */
/* #define NO_HOME_SWITCH */
/* Uncomment NO_INDEX_PULSE if you want homing sequence to
ignore the index pulse, and only use the home switch for homing.
This has the effect of making the index pulse always appear present. */
/* #define NO_INDEX_PULSE */
/* Uncomment NO_LIMIT_SWITCH if you don't have limit switches.
This has the effect of making the positive and negative travel
limit switches never appear tripped. */
/* #define NO_LIMIT_SWITCH */