This is the new replacement for the existing cortex-strings code which will
be replaced in a follow-up commit.
We should also be able to use some of the math functions to allow the
tests to pass on AArch64 (and other architectures) instead of just x86.
We might also be able to reuse some of the tests for the kyua testsuite.
Imported using
curl -L https://github.com/ARM-software/optimized-routines/tarball/e823e3abf5f89ecba58a10fc0fd82c13d9984b6b | tar --strip-components=1 -xvzf - git add .