Trivial: Clean up some typos.

Change-Id: I085615fde1f966490f30ed5d32017b8b088cfd59
Signed-off-by: Paul Vinciguerra <pvinci@vinciconsulting.com>
diff --git a/src/vnet/l2/l2_output_classify.c b/src/vnet/l2/l2_output_classify.c
index 338fe84..49a589c 100644
--- a/src/vnet/l2/l2_output_classify.c
+++ b/src/vnet/l2/l2_output_classify.c
@@ -99,7 +99,7 @@
  * @em Uses:
  * - <code>(l2_output_classify_runtime_t *)
  *         rt->classify_table_index_by_sw_if_index</code>
- *	   Head of the per-interface, perprotocol classifier table chain
+ *	   Head of the per-interface, per-protocol classifier table chain
  * 	   for a specific interface. ~0 => send pkts to the next
  * 	   feature in the L2 feature chain.
  * - <code>vnet_buffer(b)->sw_if_index[VLIB_TX]</code>