Current code compares the return pointer of function
qbman_cena_write_start with NULL. Instead the value of the return
pointer should be compared.
Signed-off-by: Pratiyush Mohan Srivastava <pratiyush.srivastava@freescale.com>
Acked-by: Prabhakar Kushwaha <prabhakar.kushwaha@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>