Bug#640499: libxvmc: please add multiarch support

[Chris Wadge <cwadge@gmail.com>]

Once i386 libraries are installed, I've found that NVidia's own 
installation scripts do an adequate job of providing the necessary 
32-bit GL libraries. This enables the expected 3D behavior one would 
expect from 32-bit WINE installations, including via PlayOnLinux. Not to 
say that this bug should not be addressed, but rather that those who 
manage their proprietary NVidia drivers outside of distro-provided 
packages should be able to use WINE normally.

For those interested, it's worth noting that the SMXI/SGFXI scripts are 
a simple way to manage proprietary drivers on Debian without much menial 
work.

All the best,
-Chris