[DOC] Clarify that single port firmware variants do not support CIP Sync and DLR

Single port EtherNet/IP firmware variants do not support CIP Sync and DLR.

This is not clearly stated in multiple documentation documents and must therefore be clarified in the following documents:

• Firmware datasheets (single port variants only)
  • Remove the following entries from "Supported features" list
    - CIP Sync
    - Device Level Ring (DLR) - Media Redundancy
  • Remove the following entries from "Predefined standard objects" list
    - Time Sync Object (0x43)
    - DLR Object (0x47)
  • Add an entry in the limitations section stating the following:
    - "CIP Sync is not supported"
    - Device Level Ring (DLR) is not supported