Update CHANGELOG, fields.yml

CHANGELOG.asciidoc

@@ -153,6 +153,7 @@ https://github.com/elastic/beats/compare/v6.4.0...master[Check the HEAD diff]
 - Support for Kafka 2.0.0 {pull}8399[8399]
 - Add container image for docker metricsets. {issue}8214[8214] {pull}8438[8438]
 - Add support for `full` status page output for php-fpm module as a separate metricset called `process`. {pull}8394[8394]
+- Add Vsphere Virtual Machine operating system to `os` field in Vsphere virtualmachine module. {pull}8543[8543]
 
 *Packetbeat*
 
@@ -606,6 +607,7 @@ https://github.com/elastic/beats/compare/v6.2.3...v6.3.0[View commits]
 - Release config reloading feature as GA. {pull}6891[6891]
 - Kubernetes deployment: Add ServiceAccount config to system metricbeat. {pull}6824[6824]
 - Kubernetes deployment: Add DNS Policy to system metricbeat. {pull}6656[6656]
+- Added 
 
 *Packetbeat*
 

metricbeat/docs/fields.asciidoc

@@ -22530,6 +22530,16 @@ type: keyword
 Virtual Machine name
 
 
+--
+
+*`vsphere.virtualmachine.os`*::
++
+--
+type: keyword
+
+Virtual Machine Operating System name
+
+
 --
 
 *`vsphere.virtualmachine.cpu.used.mhz`*::

metricbeat/module/vsphere/virtualmachine/_meta/fields.yml

@@ -12,6 +12,10 @@
       type: keyword
       description: >
         Virtual Machine name
+    - name: os
+      type: keyword
+      description: >
+        Virtual Machine Operating System name
     - name: cpu.used.mhz
       type: long
       description: >