target/hexagon: Ensure not being build on system emulation

Currently only user emulation is supported.
Assert no target code is built for system emulation.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Brian Cain <brian.cain@oss.qualcomm.com>
Message-Id: <20250121142341.17001-2-philmd@linaro.org>
1 file changed