We use GPU reference clock as a divider. Check before division that
reference clock is not zero.
Change-Id: Ie453a78b422b2e740daeb7c12ce5b06faa52ba76
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/1275743
GVS: Gerrit_Virtual_Submit
Reviewed-by: Thomas Fleury <tfleury@nvidia.com>