net/haproxy: Fix a stalled connection

This fix fixes a typo in It is a typo in the commit feca2a453
("BUG/MINOR: filters: Always set FLT_END analyzer when CF_FLT_ANALYZE flag is set").

Patch was provided on haproxy mailinglist from Christopher Faulet.

PR: 258896
Approved by: demon (maintainer)