Some variables have been initialized when used. As a result, here removes
some unncessary initial assignment.

Link: https://lore.kernel.org/r/1599547944-30671-1-git-send-email-oulijun@huawei.comSigned-off-by: NLijun Ou <oulijun@huawei.com>
Signed-off-by: NJason Gunthorpe <jgg@nvidia.com>