Use the utility function pow2ceil() for rounding up to the next
largest power of 2, rather than inline calculation.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 1437741192-20955-3-git-send-email-peter.maydell@linaro.org