hw/ppc/pnv_psi: Use device_cold_reset() instead of device_legacy_reset()

The pnv_psi.c code uses device_legacy_reset() for two purposes:
 * to reset itself from its qemu_register_reset() handler
 * to reset a XiveSource object it has

Neither it nor the XiveSource have any qbuses, so the new
device_cold_reset() function (which resets both the device and its
child buses) is equivalent here to device_legacy_reset() and we can
just switch to the new API.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20210503151849.8766-4-peter.maydell@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

hw/ppc/pnv_psi.c

@@ -466,7 +466,7 @@ static void pnv_psi_reset(DeviceState *dev)
 
 static void pnv_psi_reset_handler(void *dev)
 {
-    device_legacy_reset(DEVICE(dev));
+    device_cold_reset(DEVICE(dev));
 }
 
 static void pnv_psi_realize(DeviceState *dev, Error **errp)
@@ -710,7 +710,7 @@ static void pnv_psi_p9_mmio_write(void *opaque, hwaddr addr,
         break;
     case PSIHB9_INTERRUPT_CONTROL:
         if (val & PSIHB9_IRQ_RESET) {
-            device_legacy_reset(DEVICE(&psi9->source));
+            device_cold_reset(DEVICE(&psi9->source));
         }
         psi->regs[reg] = val;
         break;