Remove open-coded 64-bit divide

64-bit divides aren't atomic on 32-bit architectures, which in kernel
mode matters as the divide may be preempted. Ensure we only use the
kernel's helper functions to do this divide.

Bug: 154934534
Change-Id: Ib42ae56acac2cfa1b085b614efd6bc9ef462bd18
1 file changed