[Bug web/64968] Upgrade GCC Bugzilla to 5.0

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64968

--- Comment #41 from Uroš Bizjak <ubizjak at gmail dot com> ---
The GCC bugzilla favicon now shows generic Bugzilla favicon. Previously, it was
a GCC favicon.