staging: zcache: adjustments to config/build files due to renaming

[V2: no code changes, patchset now generated via git format-patch -M]

In staging/zcache, adjust config/build due to ramster->zcache renaming

Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>