QStorageInfo on Windows: fileSystemType does not distinguish network drives

If you mount a network drive on Linux, the type may be nfs or cifs (or others).

If you mount a Windows drive on OS X, the type is smbfs.

If you mount a Windows remote drive on Windows, the type is ntfs. This is not right because it doesn't allow users to distinguish network from local drives. It should be smb or cifs or something like that. To make it worse, if I share a drive from OS X (using SMB) and mount that on Windows, it still says ntfs, although the remote filesystem type is actually HFS. It's not a good cross-platform API if we can't make it behave consistently.

If getting the name of the remote-mounting protocol is not possible, then putting back some sort of flag to indicate that the drive is a network volume might be adequate for some use cases. This flag was already in place in earlier versions of what ended up as QStorageInfo.
(using Win32API GetDriveType()/ DRIVE_REMOTE), current code: qtbase\src\corelib\io\qstorageinfo_win.cpp:137 . Note that GetDriveType() is already called at to get the device name in getDevice() at qtbase\src\corelib\io\qstorageinfo_win.cpp:76 .

See https://codereview.qt-project.org/#/c/73945/41/src/corelib/io/qvolumeinfo.h https://codereview.qt-project.org/#/c/73945/41/src/corelib/io/qvolumeinfo_win.cpp and https://codereview.qt-project.org/#/c/73945/41/src/corelib/io/qvolumeinfo_unix.cpp

# 3 : QStorageInfo("name", rootPath="X:\", device="\\...\...\", fileSystemType=NTFS, [ready], bytesTotal=..., bytesFree=..., bytesAvailable=..., blockSize=-1)