docs: Update 06_Known_Issues.md for 1.2 release.

Change-Id: I7a745313e9ff5bbe11f71e38d508cb40f8cd8496
Signed-off-by: Ian Stokes <ian.stokes@intel.com>
Reviewed-by: Stephen Finucane <stephen.finucane@intel.com>
Reviewed-by: Kevin Traynor <kevin.traynor@intel.com>