Use rte_bsf32 and fast bit unset operation to optimize the
softrss computation.
The following measurements shows improvement over the default
softrss computation function.
tuple lens old(cycles) new(cycles)
3 1225 337
9 3743 992
Signed-off-by: Yangchao Zhou <zhouyates@gmail.com>
Reviewed-by: Vladimir Medvedkin <medvedkinv@gmail.com>