Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.

Fixes: 72b05b99 ("pasemi_mac: RX/TX ring management cleanup")
Fixes: 8d636d8b ("pasemi_mac: jumbo frame support")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Link: https://lore.kernel.org/r/1606903035-1838-1-git-send-email-zhangchangzhong@huawei.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>