Move target cpu tcg initialization to common code,
called from cpu_exec_realizefn.
Acked-by: NAndreas Färber <afaerber@suse.de>
Reviewed-by: NEmilio G. Cota <cota@braap.org>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>