[BUG] test/test-main.c does not compile on non-sandbox

[Heinrich Schuchardt]

Hello Simon,

commit

   c79705ea938e ("test: Move dm_test_init() into test-main.c")

merged into origin/next breaks compiling qemu-riscv64_defconfig with
CONFIG_UNIT_TEST=y:

test/test-main.c:10:10: fatal error: asm/state.h: No such file or directory
    10 | #include <asm/state.h>
       |          ^~~~~~~~~~~~~
compilation terminated.

Could you, please, provide a fix and set CONFIG_UNIT_TEST=y for some
QEMU boards so that we avoid such errors in future.

Please, also fix test/cmd/setexpr.c not compiling on non-sandbox leading
to an additional build error.

Best regards

Heinrich