[SCSI] nsp_cs: fix buf overflow

In nsp_cs_config there is a wrong struct nsp_cs_configdata allocation.
It allocates only sizeof(pointer to nsp_cs_configdata) for a whole
structure. Add a dereference to the sizeof to allocate
sizeof(nsp_cs_configdata).

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>