kernel-yocto: ensure that only valid BSPs are built
There was a bug in the search routines responsible for locating
BSP definitions which returned a valid match if only the ktype
matched.
This meant that someone looking for "qemux86foo" (which is an
invalid definition) would potentially end up building "qemuarm"
and be none the wiser (until it didn't boot).
With this fix to the tools search routine, and improved return
code testing, we will now stop the build and report and error to
the user.
[YOCTO: #11878]
Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
