exec: Include missing license in 'exec/cpu-common.h'

Commit 1ad2134f91 ("Hardware convenience library") extracted
"cpu-common.h" from "cpu-all.h", which uses the LGPL-2.1+ license.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240427155714.53669-5-philmd@linaro.org>
1 file changed