FreeBSD 10.0-RELEASE has bswap16() etc. macros defined in sys/endian.h,
which leads to a conflict with our static inline definitions.
Force using the system version of the macros.
Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Tested-by: Ed Maste <emaste@freebsd.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>