intc/xilinx_intc: Use qemu_set_irq

Use qemu_set_irq rather than if-elsing qemu_irq_(lower|raise). No
functional change, just reduces verbosity.

Cc: qemu-trivial@nongnu.org
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

hw/intc/xilinx_intc.c

@@ -66,11 +66,7 @@ static void update_irq(struct xlx_pic *p)
         i = ~0;
 
     p->regs[R_IVR] = i;
-    if ((p->regs[R_MER] & 1) && p->regs[R_IPR]) {
-        qemu_irq_raise(p->parent_irq);
-    } else {
-        qemu_irq_lower(p->parent_irq);
-    }
+    qemu_set_irq(p->parent_irq, (p->regs[R_MER] & 1) && p->regs[R_IPR]);
 }
 
 static uint64_t