Windows: Fix AFSLocateNameEntry prototype

The VolumeCB parameter is an IN/OUT parameter.

Change-Id: I3eb4231e0d095cc98cc5847905d61d924d12e6f3
Reviewed-on: http://gerrit.openafs.org/8853
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
Tested-by: Jeffrey Altman <jaltman@your-file-system.com>