[DAC] GetSyncBlockData properly count waiting threads

[max-charlamb]

Found while implementing ISOSDacInterface::GetSyncBlockData in the cDAC. #119320

The DAC version of this API is intended to iterate the SList of waiting threads with a maximum cap of 1000.
However, the pLink pointer is never actually modified in the loop so if there are any waiting threads, the API will always return the maximum cap.

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Pull Request Overview

This PR fixes a bug in the DAC (Data Access Component) implementation where the GetSyncBlockData API incorrectly counts waiting threads. The issue was that the loop iterator pLink was being assigned from the wrong source, causing an infinite loop condition that always returned the maximum cap of 1000 threads instead of the actual count.

Key Changes:

• Fixed the loop iteration logic to properly traverse the linked list of waiting threads
• Changed the assignment from pBlock->m_Link.m_pNext to pLink->m_pNext to advance the iterator

[rcj1]

LGTM