const char paths for ubik_ServerInit

const char paths for ubik_ServerInit

ubik_ServerInit* take a pathname, which should really be a const.
It already is in many of the callers, some of which remove the
const by casting, the others throw errors.

Make pathName const for all of ubik_ServerInitByInfo, ubik_ServerInit
and ubik_ServerInitCommon.
Update all of our callers to remove the now unecessary casting.
Remove the now uneccessary warning inhibition on vlserver/vlserver.c

Change-Id: I009103dc49e4473eec65ebd75aab727915c26f3c
Reviewed-on: http://gerrit.openafs.org/811
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>