libident and DST_NONE

Somebody posted here a few days ago about a problem with `conflicting
types' when building libident under NetBSD.

I just looked at the code. From what I can tell, the problem is that
libident assumes `struct timeval' refers to DST_NONE, and so it tries to
avoid using this structure when DST_NONE isn't defined. Unfortunately it
doesn't make this change everywhere it should, and so it blows up.

This is a problem for Linux with the new C library as well. An easy,
albeit not particularly neat, fix is to add -DDST_NONE to LIBIDENTCFLAGS
for systems that are afflicted like this - there's not a lot else you can
do without modifying libident. The value of DST_NONE is never used so
defining it to be empty should be harmless.

p.