VS: Add flag table entries for '/external:W*' flags in VS 16.10

Fixes: #22255
44 jobs for !6171 with vs-16.10-map-external-warnings in 8 minutes and 2 seconds (queued for 3 seconds)
latest detached
Status Job ID Name Coverage
  Build
manual #5829369
linux docker build cmake manual
build:centos6-x86_64
passed #5829366
linux docker build cmake
build:debian10-iwyu

00:03:18

manual #5829370
linux-3.17 linux docker build cmake manual
build:fedora33-ninja
passed #5829368
linux-3.17 linux docker build cmake
build:fedora33-sphinx

00:02:18

passed #5829367
docker build cmake linux-3.17 linux
build:fedora33-tidy

00:08:01

manual #5829372
nonconcurrent xcode-12.4 shell macos cmake manual
build:macos-x86_64-makefiles
manual #5829371
nonconcurrent xcode-12.4 shell macos cmake manual
build:macos-x86_64-ninja
manual #5829373
nonconcurrent msvc-19.28-16.9 vs2019 shell windows cmake manual
build:windows-vs2019-x64-ninja
 
  Test
created #5829374
x11 linux-3.17 linux docker cmake
test:fedora33-ninja
created #5829376
nonconcurrent xcode-12.4 shell macos cmake
test:macos-x86_64-makefiles
created #5829375
nonconcurrent xcode-12.4 shell macos cmake
test:macos-x86_64-ninja
created #5829377
nonconcurrent msvc-19.28-16.9 vs2019 shell windows cmake
test:windows-vs2019-x64-ninja
 
  Test Ext
created #5829380
linux docker cuda-rt cmake
test:cuda10.2-nvidia
created #5829378
linux-3.17 linux docker build cmake
test:debian10-ninja
created #5829379
linux-3.17 linux docker build cmake
test:fedora33-makefiles
created #5829381
linux-3.17 linux docker build cmake
test:fedora33-ninja-multi
created #5829382
concurrent xcode-12.4 shell macos cmake
test:macos-x86_64-xcode
created #5829383
concurrent msvc-19.28-16.9 vs2019 shell windows cmake
test:windows-vs2019-x64
 
  External
passed cdash

passed ghostflow-check-master

passed ghostflow-check-release

passed ghostflow-stager

passed cdash

passed cdash

passed cdash

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager