crypto: octeontx2 - select CONFIG_NET_DEVLINK

OcteonTX2 CPT driver will fail to link without devlink support.

aarch64-linux-gnu-ld: otx2_cpt_devlink.o: in function `otx2_cpt_dl_egrp_delete':
otx2_cpt_devlink.c:18: undefined reference to `devlink_priv'
aarch64-linux-gnu-ld: otx2_cpt_devlink.o: in function `otx2_cpt_dl_egrp_create':
otx2_cpt_devlink.c:9: undefined reference to `devlink_priv'
aarch64-linux-gnu-ld: otx2_cpt_devlink.o: in function `otx2_cpt_dl_uc_info':
otx2_cpt_devlink.c:27: undefined reference to `devlink_priv'

Fixes: fed8f4d5 ("crypto: octeontx2 - parameters for custom engine groups")

Signed-off-by: Shijith Thotton <sthotton@marvell.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>