Fixes [YOCTO #9001]
Updated the image-live class description to specifically mention
creating *.iso and *.hddimg images as "live" images. Provided more
explanation about usage through the NOISO and NOHDD variables.
Also, provided a cross-referencing link back to the updated
image-live class from the EFI_PROVIDERS variable.
(From yocto-docs rev: 788061b2911339c8396b798a0ab5635ab5bb89e1)
Signed-off-by: Scott Rifenbark <srifenbark@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>