If the user is in any directory other than $BUILDDIR when the bitbake
wrapper script is run, then show an error an exit.
Fixes [YOCTO #2071].
(From OE-Core rev: b4df1c7c79b5c801658bcf890ba3a8eab3d83189)
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>