nfp: don't pad strings in nfp_cpp_resource_find() to avoid gcc 8 warning

Once upon a time nfp_cpp_resource_find() took a name parameter,
which could be any user-chosen string.  Resources are identified
by a CRC32 hash of a 8 byte string, so we had to pad user input
with zeros to make sure CRC32 gave the correct result.

Since then nfp_cpp_resource_find() was made to operate on allocated
resources only (struct nfp_resource).  We kzalloc those so there is
no need to pad the strings and use memcmp.

This avoids a GCC 8 stringop-truncation warning:

In function ‘nfp_cpp_resource_find’,
    inlined from ‘nfp_resource_try_acquire’ at .../nfpcore/nfp_resource.c:153:8,
    inlined from ‘nfp_resource_acquire’ at .../nfpcore/nfp_resource.c:206:9:
    .../nfpcore/nfp_resource.c:108:2: warning:  strncpy’ output may be truncated copying 8 bytes from a string of length 8 [-Wstringop-truncation]
      strncpy(name_pad, res->name, sizeof(name_pad));
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>