BUG/MEDIUM: http-client/cli: Notify the http-client when the response is consumed

BUG/MEDIUM: http-client/cli: Notify the http-client when the response is consumed

In HTX mode, the "httpclient" CLI command does not use httpclient_res_xfer()
to consume the response. It dumps the HTX message stored in the http-client
response buffer and resets it by hand.

Thus, since commit b24260ec9 ("BUG/MEDIUM: http-client: Only consume input
buffer when hc one is empty"), the applet stops to consume data and is never
woken up again. The command is stuck just after the response headers, till
the server timeout expiration.

httpclient_res_consumed() is now called when the response buffer is reset.

This patch depends on :

  * MINOR: http-client: Add a function to notify some data were consumed

It must be backported as far as 3.3 with commit b24260ec9.