Conditionalize a number of components in the tree

- bootparamd
- bootpd
- finger/fingerd
- ftp/ftpd
- hastctl/hastd
- iscsid, et al
- rbootd
- talk/talkd
- tcpd, et al
- tftp/tftpd

Add src.conf entries for the various components and do a best effort
at adding components to tools/build/mk/OptionalObsoleteFiles.inc