Generally your issue is that you did a `bitbake bzImage` and that isn't a valid target name. Hence the error "make: *** No rule to make target `bzImage'. Stop.". If you want a list of the valid targets in an image do a `bitbake -g world` and then have a look at pn-buildlist.
sure?
how comes it starts compiling sources and gives you "undefined reference to `pthread_create'"?
Nope . I didn't see the mraa fail thing, that seems something else than kernel compiling... Not too sure what to recommend, can you post the do_configure.log from libmraa?