Hob: include hddimg and iso into image types.

Hob: include hddimg and iso into image types.

For image types, so far we don't include hddimg and iso. Then those files can not be deployed because they are filtered out in the image selection dialog.
This patch is to include hddimg and iso (which are "live" in image types).

Again, we have a TODO in the code for the future, that is to retrieve image types from the bitbake server instead of to use the walkaround.

(Bitbake rev: d565507940be73fb5ea3ae7048d8d143c44c2a95)

Signed-off-by: Shane Wang <shane.wang@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>