ethtool: Don't check for NULL info in prepare_data callbacks

Since commit f946270d ("ethtool: netlink: always pass genl_info to
.prepare_data") the info argument of prepare_data callbacks is never
NULL. Remove checks present in callback implementations.

Link: https://lore.kernel.org/netdev/20240703121237.3f8b9125@kernel.org/Signed-off-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20240731-prepare_data-null-check-v1-1-627f2320678f@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

net/ethtool/linkinfo.c

@@ -35,7 +35,7 @@ static int linkinfo_prepare_data(const struct ethnl_req_info *req_base,
 	if (ret < 0)
 		return ret;
 	ret = __ethtool_get_link_ksettings(dev, &data->ksettings);
-	if (ret < 0 && info)
+	if (ret < 0)
 		GENL_SET_ERR_MSG(info, "failed to retrieve link settings");
 	ethnl_ops_complete(dev);
 

net/ethtool/linkmodes.c

@@ -40,7 +40,7 @@ static int linkmodes_prepare_data(const struct ethnl_req_info *req_base,
 		return ret;
 
 	ret = __ethtool_get_link_ksettings(dev, &data->ksettings);
-	if (ret < 0 && info) {
+	if (ret < 0) {
 		GENL_SET_ERR_MSG(info, "failed to retrieve link settings");
 		goto out;
 	}

net/ethtool/strset.c

@@ -289,7 +289,6 @@ static int strset_prepare_data(const struct ethnl_req_info *req_base,
 		for (i = 0; i < ETH_SS_COUNT; i++) {
 			if ((req_info->req_ids & (1U << i)) &&
 			    data->sets[i].per_dev) {
-				if (info)
 				GENL_SET_ERR_MSG(info, "requested per device strings without dev");
 				return -EINVAL;
 			}