regsvr32 anomaly rule update

https://twitter.com/BlackMatter23/status/1417545425297580045

rules/windows/process_creation/win_susp_regsvr32_no_dll.yml

@@ -4,6 +4,7 @@ status: experimental
 description: Detects a regsvr.exe execution that doesn't contain a DLL in the command line
 author: Florian Roth
 date: 2019/07/17
+modified: 2021/07/20
 references:
     - https://app.any.run/tasks/34221348-072d-4b70-93f3-aa71f6ebecad/
 tags:
@@ -21,6 +22,8 @@ detection:
             - '.ocx'
             - '.cpl'
             - '.ax'
+            - '.bav'
+            - '.ppl'
     condition: selection and not filter
 fields:
     - CommandLine