Comment 17 for bug 1091353

Upstream TBB builds an passes testsuite fine on Aarch64:

https://launchpadlibrarian.net/165316381/buildlog_ubuntu-trusty-arm64.tbb_4.2~20130725-1.1ubuntu1_UPLOADING.txt.gz

For optimization work, I think ./include/tbb/machine/gcc_armv7.h could be used as-is on Armv8 as well?