image_types.bbclass: what's with "elf" and "cpio.gz"?

["Robert P. J. Day" <rpjday@crashcourse.ca>]

  this snippet from image_types.bbclass:

    if "elf" in alltypes:
        alltypes.remove("elf")
        if "cpio.gz" not in alltypes:
                alltypes.append("cpio.gz")
        alltypes.append("elf")

    # Filter out all the compressed images from types
    for type in alltypes:
    ... snip ...

i was going to trivially fix that comment (it's now "alltypes", not
"types"), but i was distracted by the code above that -- what the heck
is going on there?  what's the rationale for removing elf, then adding
cpio.gz and elf back on at the end?  if someone can clarify that, i
can add that as more comment, as well as a few other tweaks in that
file for more documentation for anyone reading TFS.  thanks.

rday

-- 

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Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
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