Older kernels don't have F_SETPIPE_SZ and F_GETPIPE_SZ (in
particular RHEL6's system headers don't define these). Add
ifdefs so that we can gracefully fall back to not supporting
those guest ioctls rather than failing to build.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-id: 1467304429-21470-1-git-send-email-peter.maydell@linaro.org
ddf31aa853