Otherwise you run into hilarity like trying when cross compiling a 32
bit ARM build on a 64 bit system trying to use host_cc to build 32 bit
test cases.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210512102051.12134-32-alex.bennee@linaro.org>