vlib: fix counter_will_expand prediction

vlib: fix counter_will_expand prediction

vlib_validate_combined_counter_will_expand() was calling
_vec_resize_will_expand() with wrong arguments, which resulted in false
return value. Apart from the initial call, it never indicated a vector
resize.

The callers relying on this function did not perform a barrier sync
because of the wrong prediction even if the vector got extended by
a subsequent vlib_validate_combined_counter() call.

The fix introduces a new, simplified macro that is easier to call.
vec_resize_will_expand() accepts the same arguments as vec_resize().

Type: fix
Signed-off-by: Miklos Tirpak <miklos.tirpak@gmail.com>
Change-Id: Ib2c2c8afd3e665e0e3d6ae62ff5cfa287acf670f