Remove reference to not_analyzed.

Relates #30122.

Author: jpountz

docs/reference/mapping/types/token-count.asciidoc

@@ -81,7 +81,7 @@ Defaults to `true`.
 
 <<mapping-index,`index`>>::
 
-    Should the field be searchable? Accepts `not_analyzed` (default) and `no`.
+    Should the field be searchable? Accepts `true` (default) and `false`.
 
 <<null-value,`null_value`>>::