[#2] rpc/client: Remove additional wrapper

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>

rpc/client/client.go

@@ -1,29 +1,19 @@
 package client
 
-import (
-	"sync"
-
-	"github.com/TrueCloudLab/frostfs-api-go/v2/rpc/grpc"
-)
-
 // Client represents client for exchanging messages
 // with a remote server using Protobuf RPC.
 type Client struct {
-	*cfg
-
-	gRPCClientOnce sync.Once
-	gRPCClient     *grpc.Client
+	cfg
 }
 
 // New creates, configures via options and returns new Client instance.
 func New(opts ...Option) *Client {
-	c := defaultCfg()
+	var c Client
+	c.initDefault()
 
 	for _, opt := range opts {
-		opt(c)
+		opt(&c.cfg)
 	}
 
-	return &Client{
-		cfg: c,
-	}
+	return &c
 }