Windows: .readonly space reporting

.readonly volumes can be stored on multiple partitions which each
have a different size and free space available.  To ensure consistency
regardless of which partition the .readonly is accessed from and
because .readonly volume sizes cannot change, report the allocation
size of the volume as the partition size.  Continue to report that
volume has zero free sectors because the volume cannot be written to.

Reviewed-on: http://gerrit.openafs.org/8976
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
Tested-by: Jeffrey Altman <jaltman@your-file-system.com>
(cherry picked from commit ed6354881d6f55ced842e3e78a02133fba8823ae)

Change-Id: I09bdfa8799d9871f263acdf16d00a7479c287c5d
Reviewed-on: http://gerrit.openafs.org/9051
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
Windows: Additional I/O subsystem trace messages for AFSWrite

When debugging be able to obtain additional details about the
I/O subsystem.

Reviewed-on: http://gerrit.openafs.org/8977
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
Tested-by: Jeffrey Altman <jaltman@your-file-system.com>
(cherry picked from commit 7c3f5bfba68964dfda989adb59a2b9efdb37eb4d)

Change-Id: I61af896f98314736adad3ff4f94fe6f45d6b9752
Reviewed-on: http://gerrit.openafs.org/9052
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>