exec: introduce qemu_xxhash{2,4,5,6,7}

Before moving them all to include/qemu/xxhash.h.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
4 files changed