Trivial Typo's in bier comments/docs.

Change-Id: I3b3e868277d5caf6b1341814003a3bc5726c2df9
Signed-off-by: Paul Vinciguerra <pvinci@vinciconsulting.com>
diff --git a/src/vnet/bier/bier_imp_node.c b/src/vnet/bier/bier_imp_node.c
index 727e92e..8b20325 100644
--- a/src/vnet/bier/bier_imp_node.c
+++ b/src/vnet/bier/bier_imp_node.c
@@ -143,7 +143,7 @@
                                          BIER_HDR_ENTROPY_FIELD_SHIFT);
 
                 /*
-                 * use TTL 64 for the post enacp MPLS label/BIFT-ID
+                 * use TTL 64 for the post encap MPLS label/BIFT-ID
                  * this we be decremented in bier_output node.
                  */
                 vnet_buffer(b0)->mpls.ttl = 65;