VS: Do not apply any '/external:*' flag table mapping on VS < 16.10
Since !6191 (merged) we map several /external:*
flags to their corresponding
.vcxproj
elements. These elements were added to cl.xml
in VS 16.10,
so filter them out in older VS versions. Add a field to the json flag
table format to specify the minimum version of VS needed for a given
mapping.
Issue: #22308 (closed)
Backport: release
Edited by Brad King