net/mlx4: drop live queue reconfiguration support

net/mlx4: drop live queue reconfiguration support

DPDK ensures that setup functions are never called on configured queues,
or only if they have previously been released.

PMDs therefore do not need to deal with the unexpected reconfiguration of
live queues which may fail with no easy way to recover. Dropping support
for this scenario greatly simplifies the code as allocation and setup steps
and checks can be merged.

Signed-off-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
Acked-by: Nelio Laranjeiro <nelio.laranjeiro@6wind.com>