BUG/MEDIUM: stream: Keep FLT_END analyzers if a stream detects a channel error

BUG/MEDIUM: stream: Keep FLT_END analyzers if a stream detects a channel error

If a channel error (READ_ERRO|READ_TIMEOUT|WRITE_ERROR|WRITE_TIMEOUT) is
detected by the stream, in process_stream(), FLT_END analyers must be
preserved. It is important to be sure to ends filter analysis and be able to
release the stream.

First, filters may release some ressources when FLT_END analyzers are
called. Then, the CF_FL_ANALYZE flag is used to sync end of analysis for the
request and the response. If FLT_END analyzer is ignored on a channel, this
may block the other side and freeze the stream.

This patch must be backported to all stable versions