When installing the extensible SDK we deliberately don't print the entire output of the preparation step on failure because it's very long - instead we print out the name of the file. On the autobuilder this isn't ideal though - so for the SDK test we should cat the file if the installation fails and it exists.
Patch sent to the ML, cat'ing the logfile.
Fixed in oe-core 227d2cbf9e0b8c35fa6644e3d72e0699db9607fa.