test: Do flag-processing in the correct place

test: Do flag-processing in the correct place

At present the 'ut' command handles its flags in a strange way, in that
they must come after the subcommand.

So, we must use 'ut bloblist -r2' to run the bloblist tests twice. This
is an artefact of the way tests were run, through subcommands.

It is now possible to correct this, by doing flag-processing before
running the suite.

Update the code to handle this, so that 'ut -r2 bloblist' works. Update
the 'test_suite' test to check the new arguments.

Add a sanity-check for -I while we are here.

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