DDS12 — Clarify notification of ownership change

Summary:
In section 2.1.3.9.2 EXCLUSIVE kind (the last sentence on page 2-114) the specification states that ownership changes are notified via a status change. However there is no status change that notifies of ownership change. The only way to detect it is to look at the SampleInstance and see that the publication_handle has changed.

Proposed Resolution:
Remove the sentence. We could add the Status, Listener, and Callback, but it seems unnecessary until we see some actual use-cases that require this…

Proposed Revised Text:

In section 2.1.3.9.2 EXCLUSIVE kind, last sentence in last paragraph, remove the sentence:
"The DataReader is also notified of this via a status change that is accessible by means of the Listener or Condition mechanisms."

see above