[VOL-5545] Update voltha docs

- release notes for VOLTHA versions 2.6 to 2.15 with new Jira links and adjust release schedule details
- update old links
- remove ONF references and links
- update e-mail links
- update copright notices

Change-Id: Id6be18986a8f52f2dfcc07e2b0d2efcb0ae1c0e4
Signed-off-by: serkant.uluderya <serkant.uluderya@netsia.com>
diff --git a/makefiles-orig/gerrit/help.mk b/makefiles-orig/gerrit/help.mk
index 2ba155b..5e4fe67 100644
--- a/makefiles-orig/gerrit/help.mk
+++ b/makefiles-orig/gerrit/help.mk
@@ -1,6 +1,6 @@
 # -*- makefile -*-
 # -----------------------------------------------------------------------
-# Copyright 2021-2023 Open Networking Foundation (ONF) and the ONF Contributors
+# Copyright 2021-2023 Linux Foundation Broadband Contributors
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/makefiles-orig/gerrit/include.mk b/makefiles-orig/gerrit/include.mk
index 07fac58..2af4b33 100644
--- a/makefiles-orig/gerrit/include.mk
+++ b/makefiles-orig/gerrit/include.mk
@@ -1,6 +1,6 @@
 # -*- makefile -*-
 # -----------------------------------------------------------------------
-# Copyright 2021-2023 Open Networking Foundation (ONF) and the ONF Contributors
+# Copyright 2021-2023 Linux Foundation Broadband Contributors
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -38,7 +38,7 @@
 #  IdentitiesOnly yes
 #  AddKeysToAgent yes
 #  Port 29418
-#  User tux@opennetworking.org
+#  User tux@lfbroadband.org
 # -----------------------------------------------------------------------
 
 # [EOF]