Drop rsync references for:

• ftp4.de.FreeBSD.org
• ftp.sk.FreeBSD.org
• ftp5.us.FreeBSD.org
• ftp.tr.FreeBSD.org

as they no longer offer either rsync, or FreeBSD-over-rsync.

Fix rsync paths for ftp5.se.FreeBSD.org and ftp2.uk.FreeBSD.org.