Fix uninitialized div_s64 for gcc 4.9

I know we aren't even close to using gcc 4.9, so this might not get merged
for a while, but here it is for when the time comes. :)  4.9 is even more finicky.

Missing include.

Change-Id: Ia1a0b675f37623735bc1c041fbdd0be61cdaa427
Merge remote-tracking branch 'cyan/cm-11.0' into cm-11.0