Deceptive default behavior from cert_create and fiptool bbclass.
FIP_SIGN_KEY is used to specify the rot key.
But if that key is not found (wrong path for example),
the bbclass and cert_create silently creates a new rot key,
which obviously doesn't match whatever you were using.
This is a bit annoying. If a key is specified, there is no use in believing that
the user wants a generated rot key...
If rot keys are not stored and presented during build, and for whatever reason export of keys failed or path seems wrong, this will go undetected.
Your build will succeed, but won't start.
What's worse is that you'll be stuck without a functioning fip...
