iwlwifi: move register access lock into transport

Move the reg_lock that protects HW register access
into the transport implementation. Locking is no
longer exposed, but handled internally in grab and
release NIC access. This simplifies the users.

Signed-off-by: Lilach Edelstein <lilach.edelstein@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/iwlwifi/dvm/tt.c

@@ -185,10 +185,8 @@ static void iwl_tt_check_exit_ct_kill(unsigned long data)
 			priv->thermal_throttle.ct_kill_toggle = true;
 		}
 		iwl_read32(priv->trans, CSR_UCODE_DRV_GP1);
-		spin_lock_irqsave(&priv->trans->reg_lock, flags);
-		if (iwl_trans_grab_nic_access(priv->trans, false))
-			iwl_trans_release_nic_access(priv->trans);
-		spin_unlock_irqrestore(&priv->trans->reg_lock, flags);
+		if (iwl_trans_grab_nic_access(priv->trans, false, &flags))
+			iwl_trans_release_nic_access(priv->trans, &flags);
 
 		/* Reschedule the ct_kill timer to occur in
 		 * CT_KILL_EXIT_DURATION seconds to ensure we get a