test: generator: various improvements
test: generator: various improvements

User may select number of worker threads (-w) or cpumask (-c)
(but not both) to limit number of worker thread.

Increased pool size since many threads empty the pool easily and
result some threads to give up (on the first time those see pool
empty).

Added EXAMPLE_ERR() before abort() to make debugging easier.

Signed-off-by: Petri Savolainen <d528fd253b9aaf78fa72edbcc6249e82047f6ce6@linaro.org>
Reviewed-and-tested-by: Bogdan Pricope <42ca93281c38a50e44216100dfc014dce41a2ed5@linaro.org>
Reviewed-and-tested-by: Bill Fischofer <52f3c909d51cc5d355a68a403df6906b3c1a8f83@linaro.org>
Signed-off-by: Maxim Uvarov <db4d16e02ae2d7493db430203537da8b2e34f290@linaro.org>

erachmi/odp,erachmi/odp,erachmi/odp,erachmi/odp