In addition to toggling libsnappy support, this allows a qemu-native
build to explicitly disable snappy support. When building qemu-native,
the configure script will detect libsnappy on the build machine and
improperly enable snappy support. This can corrupt the sstate cache if
the cache is populated with a qemu-native build with snappy improperly
enabled, and the cached qemu-native gets used on another build machine
that does not have libsnappy.
Signed-off-by: Robert Joslyn <robert.joslyn@redrectangle.org> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>