Turn off overflow protection for various math functions

These functions also exist as arm assembly files, where the overflows
just wrap around, and this makes their plain C equivalents behave
the same.

Bug: 32577290
Bug: 33071964
Test: ran PoC for bug 32577290 using plain C source code
Change-Id: I73c2609589e7a89d36f6c44391548312259daf14