Add a cpu_info collector

The cpu_info collector exposes a single metric per socket with some
information on installed CPUs, somewhat like the node_cpu_info metric

Signed-off-by: Steffen Higel <higels@valvesoftware.com>

docs/collector.cpu_info.md

@@ -0,0 +1,31 @@
+# cpu_info collector
+
+The cpu_info collector exposes metrics detailing a per-socket breakdown of the Processors in the system
+
+|||
+-|-
+Metric name prefix  | `cpu_info`
+Classes             | [`Win32_Processor`](https://docs.microsoft.com/en-us/windows/win32/cimwin32prov/win32-processor)
+Enabled by default? | No
+
+## Flags
+
+None
+
+## Metrics
+
+Name | Description | Type | Labels
+-----|-------------|------|-------
+`windows_cpu_info` | Labeled CPU information | gauge | `architecture`, `device_id`, `description`, `family`, `l2_cache_size` `l3_cache_size`, `name`
+
+### Example metric
+```
+windows_cpu_info{architecture="9",description="AMD64 Family 23 Model 49 Stepping 0",device_id="CPU0",family="107",l2_cache_size="32768",l3_cache_size="262144",name="AMD EPYC 7702P 64-Core Processor"} 1
+```
+The value of the metric is irrelevant, but the labels expose some useful information on the CPU installed in each socket.
+
+## Useful queries
+_This collector does not yet have any useful queries added, we would appreciate your help adding them!_
+
+## Alerting examples
+_This collector does not yet have alerting examples, we would appreciate your help adding them!_