Remove deprecated compute config options for validation-2

Below compute config options for validation server had been
deprecated with corresponding options in validation group almost
year back.
- 1908e37d2551760831e338788511db93d5129e16

    - ``compute.image_ssh_user`` (available as ``validation.image_ssh_user``)
    - ``compute.ssh_user`` (available as ``validation.image_ssh_user``)
    - ``scenario.ssh_user`` (available as ``validation.image_ssh_user``)
    - ``compute.network_for_ssh`` (available as ``validation.network_for_ssh``)
    - ``compute.ping_timeout `` (available as ``validation.ping_timeout``)

This patch removes them from tempest conf.

Few plugins still using the old configs and this depends on their fix.

Change-Id: I2221b2d50fee97a464c7d5f0b3c2e13142cb394f
diff --git a/releasenotes/notes/remove-deprecated-compute-validation-config-options-part-2-5cd17b6e0e6cb8a3.yaml b/releasenotes/notes/remove-deprecated-compute-validation-config-options-part-2-5cd17b6e0e6cb8a3.yaml
new file mode 100644
index 0000000..b4e4dd1
--- /dev/null
+++ b/releasenotes/notes/remove-deprecated-compute-validation-config-options-part-2-5cd17b6e0e6cb8a3.yaml
@@ -0,0 +1,11 @@
+---
+upgrade:
+  - |
+    Below deprecated config options from compute group have been removed.
+    Corresponding config options already been available in validation group.
+
+    - ``compute.image_ssh_user`` (available as ``validation.image_ssh_user``)
+    - ``compute.ssh_user`` (available as ``validation.image_ssh_user``)
+    - ``scenario.ssh_user`` (available as ``validation.image_ssh_user``)
+    - ``compute.network_for_ssh`` (available as ``validation.network_for_ssh``)
+    - ``compute.ping_timeout `` (available as ``validation.ping_timeout``)