include/: ignore more symlinks

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

include/.gitignore

@@ -15,6 +15,9 @@
 /dl-osinfo.h
 /fpu_control.h
 /hp-timing.h
+/jmpbuf-offsets.h
+/jmpbuf-unwind.h
+/not-cancel.h
 /pthread.h
 /semaphore.h
 /thread_db.h