ensure SDKMACHINE set properly
ensure SDKMACHINE set properly

The latest poky had a change which defaulted SDKMACHINE to the build
host architecture. Our ppc64le systems are not supported by this so it
causes builds to fail on ppc64le machines.

Upstream yocto mailing list topic on this:
https://lists.yoctoproject.org/g/yocto/message/52146

My attempts at getting this to work did not go well. Upstream was
open to supporting ppc64le but they acknowledged there is no one focused
on it at this time.

I tried a few patches but as I documented in that mailing list, I didn't
have any luck. We'll need to go with this commit to just take us back to
the default we've been using all along.

Tested: Verified builds work on ppc64le with this change

Change-Id: I7b78c51446f716634bdb9cb4bb874ff70794031e
Signed-off-by: Andrew Geissler <f7919ac9f8ec0c3ffbc3f483da625c634fd31638@yahoo.com>

openbmc/openbmc-build-scripts,openbmc/openbmc-build-scripts