iwlwifi: mvm: Fix paging memory leak

If the opmode is stopped and started again we did not free
the paging buffers. Fix that.
In addition when freeing the firmware's paging download
buffer, set the pointer to NULL.

Signed-off-by: Matti Gottlieb <[email protected]>
Signed-off-by: Emmanuel Grumbach <[email protected]>
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/fw.c b/drivers/net/wireless/intel/iwlwifi/mvm/fw.c
index 4ed5180..0ccc697 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/fw.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/fw.c
@@ -107,7 +107,7 @@
 				    sizeof(tx_ant_cmd), &tx_ant_cmd);
 }
 
-static void iwl_free_fw_paging(struct iwl_mvm *mvm)
+void iwl_free_fw_paging(struct iwl_mvm *mvm)
 {
 	int i;
 
@@ -127,6 +127,8 @@
 			     get_order(mvm->fw_paging_db[i].fw_paging_size));
 	}
 	kfree(mvm->trans->paging_download_buf);
+	mvm->trans->paging_download_buf = NULL;
+
 	memset(mvm->fw_paging_db, 0, sizeof(mvm->fw_paging_db));
 }