[yocto] [poky] RaspberryPi Layer

[Tomas Frydrych]

So, I have run into three issues with the meta-raspberrypi layer when
trying use it with Poky:

 * the libav bbappend; this can be BBMASKED on distro level, so that's
not a significant problem,

 * rpi-zram-service: a simple but rather hackish fix is to provide
rpi-zram-service-initd package that provides the same functionality for
sysvinit (not a big task) and then BBMASK it in the distro. But I am
wondering if there is some way that both -systemd and -initd packages
could be generated from the same recipe in a way that would work for
both setups so we can avoid the masking?

 * GCC seems to have issues generating armv6 code; I have run into this
bug: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47719.

Tomas