- Rename VC15 -> VC14.10, VC17 -> VC14.30.
The projects directory that holds the pre-generated Visual Studio
project files uses VC<ver> to indicate the MSVC version. At some point
support for Visual Studio 2017 (Visual Studio version 15 which uses MSVC
14.10) was added as VC15. Visual Studio 2022 (Visual Studio version 17
which uses MSVC 14.30) project files were recently added and followed
that same format using VC17.
There is no such MSVC version (yet) as VC15 or VC17.
For VS 2017 for example, the name we use is correct as either VS17,
VS2017, VC14.10. I opted for the latter since we use VC for earlier
versions (eg VC10, VC12, etc).
Ref: https://github.com/curl/curl/pull/8438#issuecomment-1037070192
Closes https://github.com/curl/curl/pull/8447
