GetVirtualServers and GetRealServers each build a result slice by
appending one entry per source element (`ipvsSvcs` and `dsts`
respectively). Pass the source length as the make() capacity so the
slice does not need to be regrown during the loop.
No behavior change.
This has been replaced by `//build:...` for a long time now.
Removal of the old build tag was automated with:
for i in $(git grep -l '^// +build' | grep -v -e '^vendor/'); do if ! grep -q '^// Code generated' "$i"; then sed -i -e '/^\/\/ +build/d' "$i"; fi; done
