tests/lcitool: Rename non-Debian specific helper

tests/lcitool: Rename non-Debian specific helper

This helper is not Debian specific, rename it to cross_build().

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220929114231.583801-10-alex.bennee@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20221028095659.48734-2-philmd@linaro.org>