s390x: Enable vector processing capability

Everything is finally in place, inform the kernel that user space
supports vector registers.
Signed-off-by: NEric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: NThomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>

target-s390x/kvm.c

@@ -269,6 +269,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
     }
 
     kvm_vm_enable_cap(s, KVM_CAP_S390_USER_SIGP, 0);
+    kvm_vm_enable_cap(s, KVM_CAP_S390_VECTOR_REGISTERS, 0);
     kvm_vm_enable_cap(s, KVM_CAP_S390_USER_STSI, 0);
 
     return 0;