SWDEV-505803 - Remove environment variable with DEBUG_*

Change-Id: I447743d1caef02592c9f0bcc21fc5569b504ee36

docs/how-to/debugging_env.rst

@@ -93,18 +93,3 @@
         the same hardware queues for the new streams in a round-robin manner. Note that this maximum
         number does not apply to hardware queues that are created for CU-masked HIP streams, or
         cooperative queues for HIP Cooperative Groups (single queue per device).
-
-    * - | ``DEBUG_HIP_7_PREVIEW``
-        | Enable preview of upcoming
-        | runtime changes that break
-        | backward compatibility.
-        | These changes might require
-        | updating existing application
-        | code to support the new
-        | behavior. The new behavior
-        | will become default in a
-        | future major release and this
-        | environment variable will
-        | no longer be needed.
-      - 0
-      - 0x1: Match the behavior of hipGetLastError with its corresponding CUDA API