buildsystem: Remove link to deleted wiki page.

As David points out, this bit of advice ("see this page for list of
packages for your distro") is probably not that helpful for a user who
has surely run into having to find a single package on their distro
already.

BUG:409659
FIXED-IN:19.08
2 jobs for master in 2 minutes and 32 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
passed #11670
smoke-test

00:01:46

passed #11669
unit-test

00:00:45