ppc/spapr: change pseries machine default to POWER10 CPU

POWER10 is the latest pseries CPU.

Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 0028ce0..b442d18 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -4664,7 +4664,7 @@
 
     smc->dr_lmb_enabled = true;
     smc->update_dt_enabled = true;
-    mc->default_cpu_type = POWERPC_CPU_TYPE_NAME("power9_v2.2");
+    mc->default_cpu_type = POWERPC_CPU_TYPE_NAME("power10_v2.0");
     mc->has_hotpluggable_cpus = true;
     mc->nvdimm_supported = true;
     smc->resize_hpt_default = SPAPR_RESIZE_HPT_ENABLED;