[DOCS] Remove basic ML terms

Author: lcawl

docs/en/stack/ml/architecture.asciidoc

@@ -1,10 +1,10 @@
-[float]
+[role="xpack"]
 [[ml-nodes]]
 === Machine learning nodes
 
 A {ml} node is a node that has `xpack.ml.enabled` and `node.ml` set to `true`,
 which is the default behavior. If you set `node.ml` to `false`, the node can
 service API requests but it cannot run jobs. If you want to use {xpackml}
 features, there must be at least one {ml} node in your cluster. For more
-information about this setting, see 
-{ref}/ml-settings.html[{ml} settings in {es}].
+information, see 
+{ref}/modules-node.html#ml-node[Machine learning node].

docs/en/stack/ml/overview.asciidoc

@@ -9,14 +9,4 @@ include::jobs.asciidoc[]
 include::datafeeds.asciidoc[]
 include::buckets.asciidoc[]
 include::calendars.asciidoc[]
-
-[[ml-concepts]]
-=== Basic Machine Learning Terms
-++++
-<titleabbrev>Basic Terms</titleabbrev>
-++++
-
-There are a few concepts that are core to {ml} in {xpack}. Understanding these
-concepts from the outset will tremendously help ease the learning process.
-
 include::architecture.asciidoc[]