crypto: nx - reduce chattiness of platform drivers

While we never would successfully load on the wrong machine type, there
is extra output by default regardless of machine type.

For instance, on a PowerVM LPAR, we see the following:

nx_compress_powernv: loading
nx_compress_powernv: no coprocessors found

even though those coprocessors could never be found.

Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Dan Streetman <ddstreet@us.ibm.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-crypto@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>