KVM: nVMX: handle page fault in vmread

commit f7eea636c3d505fe6f1d1066234f1aaf7171b681 upstream.

The implementation of vmread to memory is still incomplete, as it
lacks the ability to do vmread to I/O memory just like vmptrst.

Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>