sched: Fix for 32 bit compilation issue

Incompatible pointer type found by the compiler which
do_div need to have u64 for first parameter.

Change-Id: If44ee3569de70dd63debac46a25a96f0b558c29f
Signed-off-by: Maria Yu <aiquny@codeaurora.org>
Signed-off-by: Lingutla Chandrasekhar <clingutla@codeaurora.org>