ima: differentiate appraise status only for hook specific rules

Different hooks can require different methods for appraising a
file's integrity.  As a result, an integrity appraisal status is
cached on a per hook basis.

Only a hook specific rule, requires the inode to be re-appraised.
This patch eliminates unnecessary appraisals.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>