Revert "Provide cmd:getconf in haiku package"

This reverts commit 5558efa4ce4055b69dc416b8a9a480a229b2f3da.

We now provide getconf as a separate package from Haikuports.
Revert "Add getconf to the image"

This reverts commit c229671d8e28fbe5c81de0a10f83b22bf93a4261.
Revert "Mention getconf in FreeBSD sections in the credits."

This reverts commit d86dbc8a89dca0156b483e6643f3652055e6f01e.
Revert "Add getconf(1) from FreeBSD r259958"

This reverts commit 5a39a9feac1ed9903c099825122f0628f7944fca.