util: Add cpuinfo-aarch64.c

Move the code from tcg/.  The only use of these bits so far
is with respect to the atomicity of tcg operations.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
5 files changed