In this commit:
* add ability to create initial manifest for opkg;
* make var_map available to all backends;
(From OE-Core rev: 8d14fbedcee02b723288004ae29a5c29524eec5a)
Signed-off-by: Laurentiu Palcu <laurentiu.palcu@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>