XL build of ParaView 5.8.1 and 5.9.0 fails at curly brace initializing

@ben.boeckel

Relevant discussion here: #20253 (comment 892895)

Using ibm xlc 16.1.1.7, xlf 16.1.1.7, gcc 8.3.0, cuda-11.0 . ParaView 5.8.1 and 5.9.0 builds fail with:

In file included from .../VTK/Common/DataModel/vtkStaticCellLinksTemplate.h:162:
.../VTK/Common/DataModel/vtkStaticCellLinksTemplate.txx:359:61: error: 1540-2991 The expression is not supported.
  std::atomic<TIds>* counts = new std::atomic<TIds>[numPts] {};
                                      ^

https://www.ibm.com/support/knowledgecenter/en/SSXVZZ_16.1.1/com.ibm.xlcpp1611.lelinux.doc/language_ref/standard_features.html shows XL does not fully support std::atomic . We were not hitting this issue when vtkAtomic was used.

Edit: It looks like std::atomic is not the root cause, but the use of {} is. Possible workaround in #20454 (comment 896613)