[oe] libusb and libusb-compat: conflict

[Mike (mwester)]

There appears to be a conflict between libusb and libusb-compat -- both
stage usr/lib/libusb.a.

Many packages in OE use libusb-compat; some others use libusb.  I can't
say why this conflict hasn't come up before -- perhaps its a build order
thing that has just popped up on my system -- but attempting to link
openocd or dfu-util (which DEPEND on libusb) against the libusb.a in
staging will fail, if it was libusb-compat that was staged overtop of
libusb.

I think step one would be to put a "CONFLICTS" line in each of libusb
and libusb-compat's bb files -- but I suspect that will break a lot of
builds.  So I'll send an email out for comments and suggestions on how
to handle this little problem.

It would be good if people can check their tmpdirs to see if both libusb
and libusb-compat are being built (libusb1 is fine - not the similarity
in name).  How big a problem is this?

Regards,
Mike (mwester)