nfp: cast sizeof() to int when comparing with error code

sizeof() will return unsigned value so in the error check
negative error code will be always larger than sizeof().

Fixes: a0d8e02c ("nfp: add support for reading nffw info")
Signed-off-by: NChengguang Xu <cgxu519@gmx.com>
Acked-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/nfpcore/nfp_nffw.c

@@ -232,7 +232,7 @@ struct nfp_nffw_info *nfp_nffw_info_open(struct nfp_cpp *cpp)
 	err = nfp_cpp_read(cpp, nfp_resource_cpp_id(state->res),
 			   nfp_resource_address(state->res),
 			   fwinf, sizeof(*fwinf));
-	if (err < sizeof(*fwinf))
+	if (err < (int)sizeof(*fwinf))
 		goto err_release;
 
 	if (!nffw_res_flg_init_get(fwinf))