Remove an outdated function from the GEAR and None star formation

src/star_formation/GEAR/star_formation_logger.h

@@ -38,14 +38,6 @@
 INLINE static void star_formation_logger_log_new_spart(
     struct spart *sp, struct star_formation_history *sf) {}
 
-/**
- * @brief Initialize the star formation history struct for the stellar mass only
- *
- * @param sf the star_formation_history struct we want to initialize
- */
-INLINE static void star_formation_init_stellar_mass(
-    struct star_formation_history *sf) {}
-
 /**
  * @brief Initialize the star formation history struct in the case the cell is
  * inactive

src/star_formation/none/star_formation_logger.h

@@ -38,14 +38,6 @@
 INLINE static void star_formation_logger_log_new_spart(
     struct spart *sp, struct star_formation_history *sf) {}
 
-/**
- * @brief Initialize the star formation history struct for the stellar mass only
- *
- * @param sf the star_formation_history struct we want to initialize
- */
-INLINE static void star_formation_init_stellar_mass(
-    struct star_formation_history *sf) {}
-
 /**
  * @brief Initialize the star formation history struct in the case the cell is
  * inactive