Builds using Autotools or CMake generate config.h, thus remove the
'#ifdef HAVE_CONFIG_H'/'#endif'.
Remove also the 'add_definitions(-DHAVE_CONFIG_H)' in CMakeLists.txt.
If a CIE doesn't fit in the remainder of the mandatory part, return the
length of that remainder, so that the loop processing the CIE
terminates.
Add capture that produced the infinite loop.
Handle the I-D draft-detienne-dmvpn-01 traffic indication packet.
Print the error code in an error indication symbolically if it's a known
code.
Print the address fields in the mandatory part of the header for error
and traffic indication packets.
