Misc fixes 2 (#15190)

* Fix error when missing poller data

* Apparently impossible to detect regex without error, so require regex always.  Update docs.

* Apparently this adva code is garbage :D

* Missing count sensor type

* Processor handle missing input

* Handle missing ifName a little better

* Yep, ports module is a dumpster fire.  Attempt to clean up some.

* apparently os yaml trying to replace on non-existent fields

* Might as well define all sensor type units

* revert previous fix, real issue was vlans module does not have polling.

doc/Developing/os/Initial-Detection.md

@@ -162,7 +162,7 @@ more complex collection is required.
 - `<field>` specify an oid or list of oids to attempt to pull the data from, the first non-empty response will be used
 - `<field>_regex` parse the value out of the returned oid data, must use a named group
 - `<field>_template` combine multiple oid results together to create a final string value.  The result is trimmed.
-- `<field>_replace` An array of replacements ['find', 'replace'] or strings to remove
+- `<field>_replace` An array of replacements ['search regex', 'replace'] or regex to remove
 - `hardware_mib` MIB used to translate sysObjectID to get hardware. hardware_regex can process the result.
 
 ```yaml