Fix ZEND_BEGIN_ARG_INFO_EX for ibase_rollback_ret

When running a debug build of PHP, the engine verifies that the info
supplied in the `ZEND_BEGIN_ARG_INFO_EX` macro is correct. The last
parameter of the `ZEND_BEGIN_ARG_INFO_EX` macro is the number of
required arguments.

If we try to invoke `ibase_rollback_ret` with zero arguments, we get the
following error message:

```
Fatal error: Arginfo / zpp mismatch during call of ibase_rollback_ret() in test.php on line 123
```

This patch corrects this by setting the value to zero to match how the
method is implemented.

Author: Jon4t4n

interbase.c

@@ -103,7 +103,7 @@ ZEND_BEGIN_ARG_INFO_EX(arginfo_ibase_commit_ret, 0, 0, 1)
 	ZEND_ARG_INFO(0, link_identifier)
 ZEND_END_ARG_INFO()
 
-ZEND_BEGIN_ARG_INFO_EX(arginfo_ibase_rollback_ret, 0, 0, 1)
+ZEND_BEGIN_ARG_INFO_EX(arginfo_ibase_rollback_ret, 0, 0, 0)
 	ZEND_ARG_INFO(0, link_identifier)
 ZEND_END_ARG_INFO()
 

tests/ibase_rollback_ret_001.phpt

@@ -0,0 +1,18 @@
+--TEST--
+ibase_rollback_ret(): Make sure the method can be invoked with zero arguments
+--SKIPIF--
+<?php include("skipif.inc"); ?>
+--FILE--
+<?php
+
+require("interbase.inc");
+
+ibase_connect($test_base);
+
+ibase_query('INSERT INTO test1 VALUES (100, 2)');
+
+var_dump(ibase_rollback_ret());
+
+?>
+--EXPECTF--
+bool(true)