seemp: Port changes from 4.9 to 4.14

This patch include these changes:
- seemp: clean up stale code and add proper headers
- seemp: check array index range
- seemp: read hypervisor rooting detections
- seemp: adjust hypervisor rooting report format
- seemp: adjust interpretation of rooting report
- seemp: check validity of task struct pointer
- seemp: fix minor issues

Change-Id: I1419b583b1c2d1ba13e9661a721c5dee95484e2d
Signed-off-by: Naresh Maradana <nmardana@codeaurora.org>