Enable FIT_VERITY in the sandbox configs that build a full U-Boot
binary so CI may exercise the new dm-verity unit test
(test/boot/fit_verity.c) and the mkimage pytest
(test/py/tests/test_fit_verity.py) introduced earlier in this series.
The SPL/VPL/noinst variants only load U-Boot proper, never an OS, so
dm-verity is meaningless there and is not enabled.
Suggested-by: Tom Rini <trini@konsulko.com> Signed-off-by: Daniel Golle <daniel@makrotopia.org>