KVM: Don't wrap schedule() with vcpu_put()/vcpu_load()

Preemption notifiers will do that for us automatically.
Signed-off-by: Avi Kivity <avi@redhat.com>

virt/kvm/kvm_main.c

@@ -1689,9 +1689,7 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu)
 		if (signal_pending(current))
 			break;
 
-		vcpu_put(vcpu);
 		schedule();
-		vcpu_load(vcpu);
 	}
 
 	finish_wait(&vcpu->wq, &wait);