XF86 4 phase2 debs for PowerPC not APT-able

[Matt Brubeck <mbrubeck@hmc.edu>]

The size listed for xserver-xfree86_4.0.1-0phase2v5_powerpc.deb in
powerpc/Packages.gz is 6746112, while the actual file is 8577356 bytes.

This prevents APT from installing the package. The package installs
without problems when downloaded manually.