The error code was intended to be -EINVAL here, but it was accidentally
changed to returning success.  Set the error code.
Fixes: e53ee4acb220 ("octeontx2-af: CN20k basic mbox operations and structures")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
                         void (mbox_handler)(struct work_struct *),
                         void (mbox_up_handler)(struct work_struct *))
 {
-       int err = -EINVAL, i, dir, dir_up;
        void __iomem **mbox_regions;
        struct ng_rvu *ng_rvu_mbox;
+       int err, i, dir, dir_up;
        void __iomem *reg_base;
        struct rvu_work *mwork;
        unsigned long *pf_bmap;
                        goto free_regions;
                break;
        default:
+               err = -EINVAL;
                goto free_regions;
        }