ecryptfs: clean up attribute mess

It isn't that hard to add simple kset attributes, so don't go through
all the gyrations of creating your own object type and show and store
functions.  Just use the functions that are already present.  This makes
things much simpler.

Note, the version_str string violates the "one value per file" rule for
sysfs.  I suggest changing this now (individual files per type supported
is one suggested way.)


Cc: Michael A. Halcrow <mahalcro@us.ibm.com>
Cc: Michael C. Thompson <mcthomps@us.ibm.com>
Cc: Tyler Hicks <tyhicks@ou.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>