Wrapped process_leader.c in #ifndef DISABLE_LEADER to allow compilation with DISABLE_LEADER defined.

quantum/process_keycode/process_leader.c

@@ -14,6 +14,8 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#ifndef DISABLE_LEADER
+
 #include "process_leader.h"
 
 __attribute__ ((weak))
@@ -52,3 +54,5 @@ bool process_leader(uint16_t keycode, keyrecord_t *record) {
   }
   return true;
 }
+
+#endif