Fix for oci_fetch_assoc(): ORA-01002: fetch out of sequence warning

Fixes #1701
diff --git a/system/database/drivers/oci8/oci8_result.php b/system/database/drivers/oci8/oci8_result.php
index a2b600e..ade186b 100644
--- a/system/database/drivers/oci8/oci8_result.php
+++ b/system/database/drivers/oci8/oci8_result.php
@@ -157,7 +157,7 @@
 	protected function _fetch_assoc()
 	{
 		$id = ($this->curs_id) ? $this->curs_id : $this->stmt_id;
-		return oci_fetch_assoc($id);
+		return @oci_fetch_assoc($id);
 	}
 
 	// --------------------------------------------------------------------