Correct nvldbentry and vldbentry misuse in uss/uss_vol.c

Correct nvldbentry and vldbentry misuse in uss/uss_vol.c

The uss module relies on MapNetworkToHost / MapHostToNetwork from
src/volser.  These functions convert a struct nvldbentry and not
a struct vldbentry.  When src/volser was converted to struct nvldbentry
src/uss must have been forgotten.

In uss_vol.c convert GetServerAndPart() to accept a nvldbentry
instead of a vldbentry.

Add two static functions:

 * ovlentry_to_nvlentry() to convert from vldbentry to nvldbentry
   if required

 * uss_vol_GetEntryByID() which first attempts to use
   ubik_VL_GetEntryByIDN() and if that is not supported falls
   back to ubik_VL_GetEntryByID() and ovlentry_to_nvlentry().

LICENSE MIT

FIXES 125101

Reviewed-on: http://gerrit.openafs.org/377
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>