Issue #1919206 by vijaycs85: Create configuration schemas for syslog module.

core/modules/syslog/config/schema/syslog.schema.yml

+# Schema for the configuration files of the syslog module.
+
+syslog.settings:
+  type: mapping
+  label: 'Syslog settings'
+  mapping:
+    identity:
+      type: string
+      label: 'Identity'
+    facility:
+      type: string
+      label: 'Facility'
+    format:
+      type: string
+      label: 'Format'