This changes two scripts supporting solaris CI builds to use two
instead of one threads when building needed dependecies. This
should result in a light speedup without overloading the
Solaris builders.
Note: OpenCSW provides the builders, and the rsyslog team
is thankful for that.
Solaris does not have libfastjson packages, which we require. So we
add a script for our buildbot tests that builds its own local copy
from libfastjson git. This at least ensures we can run the buildbot
tests again on rsyslog solaris.