Makefile.in: 'distclean' target: add files and directories to remove
Merge pull request #376 from fxlb/distclean

Makefile.in: 'distclean' target: add files and directories to remove
NDOize Frame Relay, LMP and RADIUS decoders
NDOize 7 bigger decoders

This change converts IGMP, IPv6 mobility options, LDP, Lightweight
Access Point, PGM, PPTP and RIP decoders.
PGM: reuse existing AF macros