README: remove note about ARM/power hangs

Signed-off-by: Nathan Hjelm <[email protected]>

Author: hjelmn

README

@@ -17,7 +17,7 @@ Copyright (c) 2010      Oak Ridge National Labs.  All rights reserved.
 Copyright (c) 2011      University of Houston. All rights reserved.
 Copyright (c) 2013-2017 Intel, Inc. All rights reserved.
 Copyright (c) 2015      NVIDIA Corporation.  All rights reserved.
-Copyright (c) 2017      Los Alamos National Security, LLC.  All rights
+Copyright (c) 2017-2018 Los Alamos National Security, LLC.  All rights
                         reserved.
 Copyright (c) 2017      Research Organization for Information Science
                         and Technology (RIST). All rights reserved.
@@ -143,10 +143,7 @@ General notes
 Platform Notes
 --------------
 
-- ARM and POWER users may experience intermittent hangs when Open MPI
-  is compiled with low optimization settings, due to an issue with our
-  atomic list implementation.  We recommend compiling with -O3
-  optimization, both for performance reasons and to avoid this hang.
+- N/A
 
 Compiler Notes
 --------------