[PATCH v5 2/5] ntdll: Allow NtQueryVolumeInformationFile to make async volume information queries.

[Erich E. Hoover]

This patch allows NtQueryVolumeInformationFile to pass
FileFsVolumeInformation and FileFsAttributeInformation requests to the
mountmgr (as well as other device drivers).  These requests currently
do not work for NT device paths, which results in a bunch of
duplication in kernelbase (see patch 5).

v5: Fixed improper usage of io->u.Status that caused intermittent test
failures in patch 5
v4: Reordered (no content change)
v3: No change
v2: Split

Best,
Erich