iwlwifi: pcie: lock txq a bit later in reclaim code

In reclaim code, we don't need to take the queue lock for
waking the queue. The code section is executed only when
the tx path is stopped, and since the reclaim path is not
executed in parallel to itself, no one can update the queue
pointers, and accessing them is safe without a lock.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>