iwlwifi: mvm: don't call iwl_mvm_free_inactive_queue() under RCU

iwl_mvm_free_inactive_queue() will sleep in synchronize_net() under
some circumstances, so don't call it under RCU. There doesn't appear
to be a need for RCU protection around this particular call.

Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/iwlwifi.20200403112332.0f49448c133d.I17fd308bc4a9491859c9b112f4eb5d2c3fc18d7d@changeid