BUG/MEDIUM: http-ana: Only set CF_EXPECT_MORE flag on data filtering

BUG/MEDIUM: http-ana: Only set CF_EXPECT_MORE flag on data filtering

This flag is set by HTTP analyzers to notify that more data are epxected. It is
used to know if the CO_SFL_MSG_MORE flag must be set on the connection when data
are sent. Historically, it was set on chuncked messages and on compressed
responses. But in HTX, the chunked messages are parsed by the H1 multipexer. So
for this case, the infinite forwarding is enabled and the flag must no longer be
set. For the compression, the test must be extended and be applied on all data
filters. Thus it is also true for the request channel.

So, now, CF_EXPECT_MORE flag is set on a request or a response channel if there
is at least one data filter attached to the stream. In addition, the flag is
removed when the HTTP message analysis is finished.

This patch should partially fix the issue #756. It must be backported to 2.1.