Revert "Add a warning to the atrace binary for deprecating vendo..."

Revert "Update atrace host test to check stderr/stdout separately"

Revert submission 2120422-atrace_warn

Reason for revert: The atrace CLI tool will not be immediately deprecated, only the HAL.

Actually perfetto uses the atrace CLI tool and the warning message is reported as an error in captured traces.

Reverted Changes:
I9f054e6b0:Add a warning to the atrace binary for deprecating...
If91740d65:Update atrace host test to check stderr/stdout sep...

Bug: 204935495
Change-Id: If58157fdb91db7ff8d115b6efd4a424687274302