Hi!

Recently, emacs from git stopped compiling on NetBSD because it
started using pthread_setname_np. AFAIK, there is no commonly agreed
upon standard for this function, and NetBSD's uses three arguments, see
https://netbsd.gw.com/cgi-bin/man-cgi?pthread_setname_np++NetBSD-current

The attached patch makes emacs compile again (on NetBSD-9.99.43/amd64)
but configure should probably be taught to look for that version of
pthread_setname_np instead of the #ifdef __NetBSD__.

Thanks,
 Thomas