MINOR: freq_ctr: Make the sliding window sums thread-safe

swrate_add() and swrate_add_scaled() now rely on the CAS atomic operation. So
the sliding window sums are atomically updated.

(cherry picked from commit e2e8c6779e54ab86edd80697fe1e5c80633eaca6)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
1 file changed