rbd: check nbd tool features only for rbd driver

calling setRbdNbdToolFeatures inside an init
gets called in main.go for both cephfs and rbd
driver. instead of calling it in init function
calling this in rbd driver.go as this is specific
to rbd.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

internal/rbd/driver/driver.go

@@ -153,6 +153,8 @@ func (r *Driver) Run(conf *util.Config) {
 			log.FatalLogMsg(err.Error())
 		}
 		rbd.SetGlobalInt("krbdFeatures", krbdFeatures)
+
+		rbd.SetRbdNbdToolFeatures()
 	}
 
 	if conf.IsControllerServer {