lib, bgpd, tests: Refactor FILTER_X in zebra.h

lib/zebra.h has FILTER_X #define's.  These do not belong there.
Put them in lib/filter.h where they belong.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
diff --git a/bgpd/bgp_dump.c b/bgpd/bgp_dump.c
index 227fc7a..1fa0e65 100644
--- a/bgpd/bgp_dump.c
+++ b/bgpd/bgp_dump.c
@@ -27,8 +27,9 @@
 #include "prefix.h"
 #include "thread.h"
 #include "linklist.h"
-#include "bgpd/bgp_table.h"
+#include "filter.h"
 
+#include "bgpd/bgp_table.h"
 #include "bgpd/bgpd.h"
 #include "bgpd/bgp_route.h"
 #include "bgpd/bgp_attr.h"