sbsa-ref: switch default cpu core to Neoverse-N1

The world outside moves to newer and newer cpu cores. Let move SBSA
Reference Platform to something newer as well.

Signed-off-by: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
Message-id: 20230506183417.1360427-1-marcin.juszkiewicz@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/arm/sbsa-ref.c

@@ -852,7 +852,7 @@ static void sbsa_ref_class_init(ObjectClass *oc, void *data)
 
     mc->init = sbsa_ref_init;
     mc->desc = "QEMU 'SBSA Reference' ARM Virtual Machine";
-    mc->default_cpu_type = ARM_CPU_TYPE_NAME("cortex-a57");
+    mc->default_cpu_type = ARM_CPU_TYPE_NAME("neoverse-n1");
     mc->max_cpus = 512;
     mc->pci_allow_0_address = true;
     mc->minimum_page_bits = 12;