gitlab: Enable cross-i386 builds of TCI

We're currently only testing TCI with a 64-bit host -- also test
with a 32-bit host.  Enable a selection of softmmu and user-only
targets, 32-bit LE, 64-bit LE, 32-bit BE, as there are ifdefs for each.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210502235727.1979457-27-richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>