afs: Consolidate ShakeLooseVCaches retry init

afs: Consolidate ShakeLooseVCaches retry init

Don't duplicate the initialization code in effectively three separate
places. Just goto the top of the loop again.

This should incur no functional change; it's just reorganization.

Change-Id: I40548919a5fa9c4e472a4de0eada8d213d034097
Reviewed-on: http://gerrit.openafs.org/8848
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Chas Williams - CONTRACTOR <chas@cmf.nrl.navy.mil>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>