CI: FAT runtime build tests on SSE2 machine

[byeonguk-jeong]

SSE2 machines do not support FAT runtime, as it requires SSSE3 features.
CI runs some FAT tests on SSE2 machines, making failures unexpectedly.

See: https://buildbot-ci.vectorcamp.gr/#/builders/233/builds/230

[markos]

@byeonguk-jeong Sorry I was away and with little net access. We enabled SSE2 support using SIMDe library to emulate missing instructions and make the library usable on older machines. This is not a mistake, all PRs should also pass that.