staging: octeon: Remove unneeded variable

Remove unneeded variable used to store return value. Issue found by
coccicheck.

Signed-off-by: Cristiane Naves <cristianenavescardoso09@gmail.com>
Link: https://lore.kernel.org/r/20191026222453.GA14562@cristiane-Inspiron-5420


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>