Remove nonsensical bozon-lock defines

Remove nonsensical bozon-lock defines

Currently there are two preprocessor defines related to bozon locks:
AFS_BOZONLOCK_ENV, and AFS_NOBOZO_LOCK. The former creates the pvnLock
member of a struct vcache, and controls calls to e.g. afs_BozonLock in
cross-platform code. The latter, if defined, turns calls to e.g.
afs_BozonLock into no-ops.

It doesn't make any sense to have both of these, since if
AFS_BOZONLOCK_ENV and AFS_NOBOZO_LOCK are defined, the pvnLock member
exists but is never used, since afs_BozonLock &co are no-ops. On
Solaris, the only platform where AFS_NOBOZO_LOCK is currently defined
(DUX used to define it before DUX was dropped), this is the case.

So to make things a bit more clear, get rid of the AFS_NOBOZO_LOCK
define, and just use AFS_BOZONLOCK_ENV to dictate whether we do
anything with bozon locks (ppc_darwin_80 appears to be the only
platform at this time).

Remove AFS_BOZONLOCK_ENV from Solaris param files, since it doesn't
use bozon locks. Remove all references to pvnLock in Solaris-specific
code.

Change-Id: Id72c14ec5485d35b853d38e2ea1a944a385f2b5b
Reviewed-on: http://gerrit.openafs.org/4889
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>