afs: Treat vc_error as a CheckCode-translated code

The vcache field vc_error is generally treated as an error code that
has been translated through afs_CheckCode, but this is inconsistent in
a few places. Fix this in a few ways:

 - Adjust afs_nfsrdwr so we do not call afs_CheckCode on vc_error,
   translating the error code twice.

 - Change afs_close to store vc_error in code_checkcode, and have the
   logging code check for specific values in code_checkcode as well.
   Log unknown values of code and code_checkcode, so we can
   distinguish between e.g. a 'code' value of VBUSY, and a
   'code_checkcode' value of ETIMEDOUT.

Change-Id: Iab4928efd183fb6c5b0b0f30375b9952ba13b45a
Reviewed-on: http://gerrit.openafs.org/10634
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: Derrick Brashear <shadow@your-file-system.com>
afs: Fix afs_CheckCode identifier collision

The last argument to afs_CheckCode should be unique so the call site
can be identified if fstrace is turned on. BStore and BPartialStore
were both using 43, so change BPartialStore to 430 to avoid the
collision.

Change-Id: I81a43ee41623fad10d0e70a7d9c8e6029aba30eb
Reviewed-on: http://gerrit.openafs.org/10635
Reviewed-by: Perry Ruiter <pruiter@sinenomine.net>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
afs: Translate VNOSERVICE to ETIMEDOUT

Some fileservers will kill calls that are taking too long with the
VNOSERVICE abort code. Our logic for retrying calls is already aware
of this usage, but if we cannot retry the call, we still just return
VNOSERVICE as an error code to our caller.

Don't return this raw, since has the same value as ENOBUFS, which can
cause a confusing error message from logs or applications ("No buffer
space available"). Return ETIMEDOUT instead.

Change-Id: Ic16422585a10cda7f21646a27c92f690b131ce9b
Reviewed-on: http://gerrit.openafs.org/10766
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: Andrew Deason <adeason@sinenomine.net>