The NIOS2 softcore does not implement the __sync_add_and_fetch_8,
so disable it accordingly.
Signed-off-by: Marek Vasut <marex@denx.de> Cc: Ley Foon Tan <lftan@altera.com> Cc: Richard Purdie <richard.purdie@linuxfoundation.org> Cc: Ross Burton <ross.burton@intel.com> Cc: Thomas Chou <thomas@wytron.com.tw> Cc: Walter Goossens <waltergoossens@home.nl> Signed-off-by: Ross Burton <ross.burton@intel.com>
