remove deprecated and unmaintained voltha-adapter-simulated helm chart

* the applications to simulate a voltha onu and olt adapter have been
  deprecated with VOLTHA 2.3 with the specific flag "No Maintenance
  Intended"
  * https://github.com/opencord/voltha-simolt-adapter
  * https://github.com/opencord/voltha-simonu-adapter
* the vOLTHA TST confirmed that this helm chart (which can be used to
  deploy the aforementioned applications) has not been used for a
  long time and it is safe to remove it
* this commit removes the complete helm chart voltha-adapter-simulated
  without a replacement
* increase Chart version of voltha helm chart since the jenkins pipeline
  linter does require this change, although it is not necessary in this
  context since the change does not affect the voltha helm chart

Change-Id: I219ead3dccfd9789ec3f270c7c3fdc11de841a3a
Signed-off-by: Jan Klare <jan.klare@bisdn.de>
diff --git a/voltha/Chart.yaml b/voltha/Chart.yaml
index 1a5a6dc..05bb6b4 100644
--- a/voltha/Chart.yaml
+++ b/voltha/Chart.yaml
@@ -14,7 +14,7 @@
 ---
 apiVersion: "v1"
 name: "voltha"
-version: "2.12.6"
+version: "2.12.7"
 description: "A Helm chart for Voltha based on K8S resources in Voltha project"
 keywords:
   - "onf"