Fix #50444: PDO-ODBC changes for 64-bit

[This bug](https://bugs.php.net/bug.php?id=50444) is also referenced in [#61777](https://bugs.php.net/bug.php?id=61777) and is still present in the latest stable release of the 5.5 branch (it looks like it's existed since at least 5.2). I see two tickets exist for this problem already, and I'm just submitting these changes via github as a reminder that this is a serious problem for anyone using PDO_ODBC on the 64-bit builds (any query with bound parameters will segfault).

I built my [feature branch](https://github.com/Andrewpk/php-src/tree/pdo_odbc_x64_fix) and verified that this fixed the bound parameters problem when using 64bit php + pdo_odbc basing off of 5.5.9 release. All other tests passed as they did for the 5.5.9 release. Patches for this already exist in the reported bugs, but I'm just sending a PR to voice my concern and re-propose the already proposed changes in case they've been forgotten.

Currently, the only workaround solutions for 64-bit users who utilize pdo_odbc are:
- Maintain their own builds of php with this or similar patches applied
- Run a 32-bit install of both php and the odbc manager (either with 32bit compat libs or chroot environment)

Thank you very much for all of your hard work!
I really enjoy the 5.5 improvements.