[yocto] why does meta-yocto prepend to BBPATH, while meta-yocto-bsp appends?

[Robert P. J. Day]

  i know i asked this way back when but i forget the answer -- why
does meta-yocto layer.conf prepend to BBPATH:

  BBPATH =. "${LAYERDIR}:"

while meta-yocto-bsp appends:

  BBPATH .= ":${LAYERDIR}"

rday

-- 

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

Twitter:                                       http://twitter.com/rpjday
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