Update breaking-8.0.asciidoc (#30565)

Co-authored-by: DeDe Morton <[email protected]>

libbeat/docs/release-notes/breaking/breaking-8.0.asciidoc

@@ -63,6 +63,26 @@ Starting with version 8.0.0, Elastic no longer publishes Homebrew formulae for
 the https://www.elastic.co/downloads/beats/[{beats} download pages]
 for available installation methods.
 
+
+[discrete]
+==== Removal of older platforms from {beats} support matrix
+Starting with version 8.0.0, the following operating systems are no longer supported
+by {beats} due to lack of vendor support for the operating system. In order to have
+the best product experience, you are encouraged to move to a vendor-supported 
+version of the operating system.
+
+.*These platforms are:*
+* Centos 6
+* Centos 8
+* RHEL 6
+* Ubuntu 14.04
+* Ubuntu 16.04
+* Debian 8
+* Windows 7 SP1
+* Windows Server 2008 R2
+* MacOS 10.13
+* MacOS 10.14
+
 // end::notable-breaking-changes[]