s390x/cpumodel: default enable bpb and ppa15 for z196 and later

Most systems and host kernels provide the necessary building blocks for
bpb and ppa15. We can reverse the logic and default enable those
features, while still allowing to disable it via cpu model.

So let us add bpb and ppa15 to z196 and later default CPU model for the
qemu 3.0 machine. (like -cpu z13).  Older machine types (e.g.
s390-ccw-virtio-2.12) will retain the old value and not provide those
bits in the default model.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Message-Id: <20180626123830.18282-1-borntraeger@de.ibm.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

hw/s390x/s390-virtio-ccw.c

@@ -824,6 +824,8 @@ DEFINE_CCW_MACHINE(3_0, "3.0", true);
 static void ccw_machine_2_12_instance_options(MachineState *machine)
 {
     ccw_machine_3_0_instance_options(machine);
+    s390_cpudef_featoff_greater(11, 1, S390_FEAT_PPA15);
+    s390_cpudef_featoff_greater(11, 1, S390_FEAT_BPB);
 }
 
 static void ccw_machine_2_12_class_options(MachineClass *mc)

target/s390x/gen-features.c

@@ -512,6 +512,8 @@ static uint16_t default_GEN11_GA1[] = {
     S390_FEAT_IPTE_RANGE,
     S390_FEAT_ACCESS_EXCEPTION_FS_INDICATION,
     S390_FEAT_GROUP_MSA_EXT_4,
+    S390_FEAT_PPA15,
+    S390_FEAT_BPB,
 };
 
 #define default_GEN11_GA2 EmptyFeat