vlib rename vlib_frame_args(...) to vlib_frame_scalar_args(..)

Typically we have scalar_size == 0, so it doesn't matter
but vlib_frame_args was providing pointer to scalar frame
data, not vector data. To avoid future confusion function
is renamed to vlib_frame_scalar_args(...)

Change-Id: I48b75523b46d487feea24f3f3cb10c528dde516f
Signed-off-by: Damjan Marion <damarion@cisco.com>
diff --git a/src/vlib/node.c b/src/vlib/node.c
index c87400d..88185ce 100644
--- a/src/vlib/node.c
+++ b/src/vlib/node.c
@@ -529,7 +529,7 @@
   u16 n_vectors = frame->n_vectors;
 
   vlib_node_increment_counter (vm, node->node_index, 0, n_vectors);
-  vlib_buffer_free (vm, vlib_frame_args (frame), n_vectors);
+  vlib_buffer_free (vm, vlib_frame_vector_args (frame), n_vectors);
   vlib_frame_free (vm, node, frame);
 
   return n_vectors;