bsps/sparc: Fix link-time error

Fix for commit 76ac1ee3bb.

c/src/lib/libbsp/sparc/shared/timer/tlib_ckinit.c

@@ -135,16 +135,10 @@ void Clock_isr(void *arg_unused)
   } while ( _Thread_Executing == _Thread_Idle &&
           _Thread_Heir == _Thread_Executing);
 
-  Clock_driver_support_at_tick();
   return;
 
 #else
 
-  /*
-   * Add custom handling at every tick from bsp.h
-   */
-  Clock_driver_support_at_tick();
-
 #ifdef CLOCK_DRIVER_ISRS_PER_TICK
   /*
    *  The driver is multiple ISRs per clock tick.