cpufreq: schedutil: fix undefined reference to '__aeabi_uldivmod'

Division of a 64 bit variable isn't supported by the "/" operator in
a 32-bit architecture. So, use do_div() instead.

Change-Id: Id07ce36166ee1ee88ff6519dc26724c4e847890b
Signed-off-by: Maria Yu <aiquny@codeaurora.org>
Signed-off-by: Jonathan Avila <avilaj@codeaurora.org>