be build WITH_THREADS on recent versions of FreeBSD once again) [1]; rename
*.core files in sbcl and math/maxima so that they are not removed by
disk-cleaning scripts [2]; make it possible to use the makesum target in sbcl
WITH_SBCL; fix maxima build WITH_CMUCL, and place a default memory cap of
1GiB on amd64; reduce default output from a few targets in maxima, and defer
patch cleaning to the pre-build target to make debugging easier
PR: 162017 [1], 162680 [2]
Approved by: pav (portmgr)
Feature safe: yes
