Remove SNMP metrics from default polling

These metrics are no longer supported since we removed
GenericHardwareDeclarativePollster by [1].

[1] a28cef7036

Closes-Bug: #2007108
Change-Id: I2437f311ae0f975570c7b01bfa0f045af7cfeab4

etc/ceilometer/polling.yaml

@@ -14,21 +14,3 @@ sources:
         - disk.device.read.requests
         - disk.device.write.bytes
         - disk.device.write.requests
-        - hardware.cpu.util
-        - hardware.cpu.user
-        - hardware.cpu.nice
-        - hardware.cpu.system
-        - hardware.cpu.idle
-        - hardware.cpu.wait
-        - hardware.cpu.kernel
-        - hardware.cpu.interrupt
-        - hardware.memory.used
-        - hardware.memory.total
-        - hardware.memory.buffer
-        - hardware.memory.cached
-        - hardware.memory.swap.avail
-        - hardware.memory.swap.total
-        - hardware.system_stats.io.outgoing.blocks
-        - hardware.system_stats.io.incoming.blocks
-        - hardware.network.ip.incoming.datagrams
-        - hardware.network.ip.outgoing.datagrams

releasenotes/notes/bug-2007108-dba7163b245ad8fd.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    [`bug 2007108 <https://bugs.launchpad.net/ceilometer/+bug/2007108>`_]
+    The retired metrics dependent on SNMP have been removed from the default
+    ``polling.yaml``.