vol: Move VOL_CV_TIMEDWAIT to volume_inline.h

vol: Move VOL_CV_TIMEDWAIT to volume_inline.h

Some platforms will give errors for the vol package glock not being
defined in VOL_CV_TIMEDWAIT, since some utilities include volume.h
(with pthreaded ubik enabled) but do not have the vol glock. This
isn't a problem for the other CV_WAIT (et al) macros, since, being
macros, they are not expanded if never referenced. Since
VOL_CV_TIMEDWAIT is a static inline function, however, and at least
some platforms try to compile/link it even if it's not referenced.

So, move it to volume_inline.h, which is only used by the volume
package itself, where we will have the vol glock.

Change-Id: I3e1513869c03d16d274c23e0bbb075df85d6d3a3
Reviewed-on: http://gerrit.openafs.org/3363
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: BuildBot <buildbot@rampaginggeek.com>