Remove use of tail for 'make depend'.

Not every tail supports +N and we can do with out it so just remove it.
Prompted by mforney at mforney.org.

Makefile.in

@@ -350,10 +350,11 @@ depend: depend-rebuild
 	rm -f .depend.bak
 
 depend-rebuild:
-	rm -f config.h
-	touch config.h
+	rm -f config.h .depend
+	touch config.h .depend
 	makedepend -w1000 -Y. -f .depend *.c 2>/dev/null
-	(head -2 .depend; tail +3 .depend | sort) >.depend.tmp
+	(echo '# Automatically generated by makedepend.'; \
+	 echo '# Run "make depend" to rebuild.'; sort .depend ) >.depend.tmp
 	mv .depend.tmp .depend
 	rm -f config.h