ip: allocate ip4 mtrie pages in htlb memory

No change in default behavior. To use htlb pages for the ip4 mtrie,
use the "ip" command-line option "mtrie-hugetlb".

Type: improvement

Signed-off-by: Dave Barach <dave@barachs.net>
Change-Id: I5497e426a47200edff2c7e15563ed6a42af12e7f
diff --git a/src/vnet/ip/ip4.h b/src/vnet/ip/ip4.h
index b5bc2e2..f5ed938 100644
--- a/src/vnet/ip/ip4.h
+++ b/src/vnet/ip/ip4.h
@@ -167,6 +167,9 @@
   /** Heapsize for the Mtries */
   uword mtrie_heap_size;
 
+  /** Use hugetlb pages for the Mtries */
+  int mtrie_hugetlb;
+
   /** The memory heap for the mtries */
   void *mtrie_mheap;