classes/populate_sdk_ext: make it clear when SDK installation has failed
When SDK preparation fails:
* Insert an ERROR: in front of the error message
* Add an error message to the environment setup script
Hopefully this should make it more obvious when this happens.
Fixes [YOCTO #8658].
(From OE-Core master rev:
105df569b3b1982005c2edb37f4690f9ba6bde35)
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
