fix misspell (tikv#1135)

Signed-off-by: Weizhen Wang <wangweizhen@pingcap.com>

config/client.go

@@ -60,7 +60,7 @@ type TiKVClient struct {
 	// GrpcCompressionType is the compression type for gRPC channel: none or gzip.
 	GrpcCompressionType string `toml:"grpc-compression-type" json:"grpc-compression-type"`
 	// GrpcSharedBufferPool is the flag to control whether to share the buffer pool in the TiKV gRPC clients.
-	GrpcSharedBufferPool bool `toml:"grpc-shared-buffer-pool" json:"ggrpc-shared-buffer-pool"`
+	GrpcSharedBufferPool bool `toml:"grpc-shared-buffer-pool" json:"grpc-shared-buffer-pool"`
 	// CommitTimeout is the max time which command 'commit' will wait.
 	CommitTimeout string      `toml:"commit-timeout" json:"commit-timeout"`
 	AsyncCommit   AsyncCommit `toml:"async-commit" json:"async-commit"`