Revert/optimize some changes from 48a2baf0e288accd206f5da5031d29076e130792
diff --git a/system/database/drivers/mssql/mssql_driver.php b/system/database/drivers/mssql/mssql_driver.php
index 5bd6669..697b2fd 100644
--- a/system/database/drivers/mssql/mssql_driver.php
+++ b/system/database/drivers/mssql/mssql_driver.php
@@ -64,7 +64,7 @@
 	 */
 	public function db_connect()
 	{
-		if ($this->port !== '')
+		if ( ! empty($this->port))
 		{
 			$this->hostname .= ','.$this->port;
 		}
@@ -81,7 +81,7 @@
 	 */
 	public function db_pconnect()
 	{
-		if ($this->port !== '')
+		if ( ! empty($this->port))
 		{
 			$this->hostname .= ','.$this->port;
 		}