qlcnic: multi protocol internal loopback support added.

Driver will generate loopback traffic pattern and do the test. And
returns result of the test to application.

Updated driver version to 5.0.19.

Signed-off-by: Sucheta Chakraborty <sucheta.chakraborty@qlogic.com>
Signed-off-by: Anirban Chakraborty <anirban.chakraborty@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>