[cacao] mmap first page

[Stefan Ring]

> With the latest changeset [1] I finally disabled the mmap of the first
> page in our trap handling code by default. Note that this also
> obsoletes IcedTea's 'cacao-no-mmap-first-page' patch.

IcedTea uses the 0.99.4 release tarball, so the patch will still need
to stay there for quite a while. I've been thinking about making
IcedTea pull directly from Mercurial; after all, it does exactly that
for all the OpenJDK stuff it pulls.