selftest/meta_ide: source the environment first, then change to the sources directory
This too used to work by coincidence: sourcing the environment
quietly failed without changing to the build directory, but
now that it works properly, things should be done in correct order.
(From OE-Core rev: ed98173057fa128ff565e1e1078b150ca14a85e0)
Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>