CLEANUP: Replace repeated code to count usable servers with be_usable_srv()

2 places were using an open-coded implementation of this function to count
available servers. Note that the avg_queue_size() fetch didn't check that
the proxy was in STOPPED state so it would possibly return a wrong server
count here but that wouldn't impact the returned value.

Signed-off-by: Nenad Merdanovic <nmerdan@haproxy.com>
1 file changed