crypto: nx - Fixing NX data alignment with nx_sg list

crypto: nx - Fixing NX data alignment with nx_sg list

In NX we need to pass always a 16 multiple size nx_sg_list to
co processor. Trim function handle with this assuring all nx_sg_lists
are 16 multiple size, although data was not being considerated when
crop was done. It was causing an unalignment between size of the list
and data, corrupting csbcpb fields returning a -23 H_ST_PARM error, or
invalid operation.

This patch fix this recalculating how much data should be put back
in to_process variable what assures the size of sg_list will be
correct with size of the data.

Signed-off-by: Leonidas S. Barbosa <leosilva@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>