kvm: Mark VCPU state dirty on creation

This avoids that early cpu_synchronize_state calls try to retrieve an
uninitialized state from the kernel. That even causes a deadlock if
io-thread is enabled.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

kvm-all.c

@@ -211,6 +211,7 @@ int kvm_init_vcpu(CPUState *env)
 
     env->kvm_fd = ret;
     env->kvm_state = s;
+    env->kvm_vcpu_dirty = 1;
 
     mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
     if (mmap_size < 0) {