Remove c-11 memcpy checks from perf-critical code

Change-Id: Id4f37f5d4a03160572954a416efa1ef9b3d79ad1
Signed-off-by: Dave Barach <dave@barachs.net>
diff --git a/src/vppinfra/fifo.c b/src/vppinfra/fifo.c
index e3b7b41..e97b2c3 100644
--- a/src/vppinfra/fifo.c
+++ b/src/vppinfra/fifo.c
@@ -112,11 +112,11 @@
       if (head + n_copy_bytes >= end)
 	{
 	  uword n = end - head;
-	  clib_memcpy (v_new, head, n);
-	  clib_memcpy (v_new + n, v_old, n_copy_bytes - n);
+	  clib_memcpy_fast (v_new, head, n);
+	  clib_memcpy_fast (v_new + n, v_old, n_copy_bytes - n);
 	}
       else
-	clib_memcpy (v_new, head, n_copy_bytes);
+	clib_memcpy_fast (v_new, head, n_copy_bytes);
     }
 
   /* Zero empty space. */