This patch fix compilation error in 32-bit ARM architecture regarding
division of 2 64-bit variables.

Use the kernel do_div() macro, which is implemented per architecture, for
doing these divisions instead of using the / operator.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>