IB/iser: add safety checks for state_mutex lock

In some cases, we need to make sure that state_mutex is taken. Use
lockdep_assert_held to warn us in case it doesn't while it should.

Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Link: https://lore.kernel.org/r/20221016093833.12537-3-mgurtovoy@nvidia.com


Reviewed-by: Sergey Gorenko <sergeygo@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Leon Romanovsky <leon@kernel.org>