fib: fix some typos in fib/mtrie

Type: fix

Change-Id: I1af0e4a9bc23a3b6b6d3a74df093801ab6cae1f8
Signed-off-by: Lijian Zhang <Lijian.Zhang@arm.com>
diff --git a/src/vnet/devices/pipe/pipe.h b/src/vnet/devices/pipe/pipe.h
index ef72934..7a64e9c 100644
--- a/src/vnet/devices/pipe/pipe.h
+++ b/src/vnet/devices/pipe/pipe.h
@@ -19,7 +19,7 @@
 #include <vnet/ethernet/ethernet.h>
 
 /**
- * represenation of a pipe interface
+ * representation of a pipe interface
  */
 typedef struct pipe_t_
 {