md5c.c is broken on amd64

[Doug Barton]

Steve Kargl wrote:

> I didn't do a buildworld.  It appears that one can no longer
> rebuild only a part of the tree. 

One can usually do so if one has a fairly up to date buildworld in place
already.

> On the bright, I found I have a boat loader of bitrot in /usr/include.

It's usually a good idea to 'mv /usr/include /usr/include-old' before
installworld. It's also usually helpful to 'rm -r /usr/share/man/*' before
installworld as well.

Doug