arm/xilinx-zynq: Do not provide legacy API

The header file <rtems/irq.h> provides a legacy API.  Do not provide it
by default through <bsp/irq.h>.

bsps/arm/shared/clock/clock-a9mpcore.c

@@ -48,7 +48,7 @@
 static struct timecounter a9mpcore_tc;
 
 /* This is defined in dev/clock/clockimpl.h */
-void Clock_isr(rtems_irq_hdl_param arg);
+void Clock_isr(void *arg);
 
 __attribute__ ((weak)) uint32_t a9mpcore_clock_periphclk(void)
 {

bsps/arm/xilinx-zynq/include/bsp/irq.h

@@ -36,7 +36,6 @@
 
 #ifndef ASM
 
-#include <rtems/irq.h>
 #include <rtems/irq-extension.h>
 
 #include <bsp/arm-a9mpcore-irq.h>