bsps: Avoid rtems_irq_hdl_param type usage

Not every clock interrupt service routine is installed with this API.
Remove also the prototype to allow drivers to make this routine static.

c/src/lib/libbsp/shared/clockdrv_shell.h

@@ -57,8 +57,7 @@ void Clock_exit( void );
  *  Return values:      NONE
  */
 #ifdef BSP_FEATURE_IRQ_EXTENSION
-void Clock_isr(rtems_irq_hdl_param arg);
-void Clock_isr(rtems_irq_hdl_param arg)
+void Clock_isr(void *arg)
 {
 #else 
 rtems_isr Clock_isr(rtems_vector_number vector);