[OE-core] SDK does not contain pkg-config files

[Mike Looijmans]

I'm trying to get the SDK to work, but no success because the SDK apparently 
does not install any pkg-config file, resulting in autotools and cmake not 
being able to find any library.

Built the SDK using "bitbake -c populate_sdk image"

Install the resulting SDK, and source the shell script.

Building "helloworld" works. Building something slightly more advanced fails, 
because pkg-config isn't working: "pkg-config --list-all" is empty.

The cause is that the pkgconfig files simply aren't in the sysroot:

$ echo $PKG_CONFIG_PATH
/home/mike/p/sysroots/cortexa9t2hf-neon-oe-linux-gnueabi/usr/lib/pkgconfig:/home/mike/p/sysroots/cortexa9t2hf-neon-oe-linux-gnueabi/usr/share/pkgconfig
$ ls /home/mike/p/sysroots/cortexa9t2hf-neon-oe-linux-gnueabi/usr/lib/pkgconfig
ls: cannot access 
'/home/mike/p/sysroots/cortexa9t2hf-neon-oe-linux-gnueabi/usr/lib/pkgconfig': 
No such file or directory
$ ls /home/mike/p/sysroots/cortexa9t2hf-neon-oe-linux-gnueabi/usr/share/pkgconfig
ls: cannot access 
'/home/mike/p/sysroots/cortexa9t2hf-neon-oe-linux-gnueabi/usr/share/pkgconfig': 
No such file or directory