sandbox: Create a new sandbox_noinst build

Move sandbox_spl over to use OF_PLATDATA_INST. Create a new board to
test the case when this is not enabled, since we will be keeping that
code around for several months and want to avoid regressions.

Skip the dm_test_of_plat_dev() test since driver info is not available
for OF_PLATDATA_INST.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>