'err' will be assigned later and cleanup the redundant initialization.

Cc: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NShaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>