get_bb_var() currently end up calling 'bitbake -e' and parsing the whole
output. However if postconfig isn't set then we can speed this up by
just calling bitbake-getvar.
The complication with failing bitbake-getvar calls is because we need to
be careful to return None instead of the empty string when the variable
doesn't exist.
(From OE-Core rev: fafe77879aa6225aa8b5187ff590bb4998cbf987)
Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
55c4f54106