Added support for runtime level snapshotter, issue 6657

Signed-off-by: shuaichang <shuai.chang@databricks.com>

Updated annotation name

pkg/cri/config/config.go

@@ -71,6 +71,11 @@ type Runtime struct {
 	// be loaded from the cni config directory by go-cni. Set the value to 0 to
 	// load all config files (no arbitrary limit). The legacy default value is 1.
 	NetworkPluginMaxConfNum int `toml:"cni_max_conf_num" json:"cniMaxConfNum"`
+	// Snapshotter setting snapshotter at runtime level instead of making it as a global configuration.
+	// An example use case is to use devmapper or other snapshotters in Kata containers for performance and security
+	// while using default snapshotters for operational simplicity.
+	// See https://github.com/containerd/containerd/issues/6657 for details.
+	Snapshotter string `toml:"snapshotter" json:"snapshotter"`
 }
 
 // ContainerdConfig contains toml config related to containerd