CLEANUP: connection: Remove CS_FL_READ_PARTIAL flag

Since the recent refactoring of the H1 multiplexer, this flag is no more
used. Thus it is removed.
diff --git a/contrib/debug/flags.c b/contrib/debug/flags.c
index d845e4e..044221e 100644
--- a/contrib/debug/flags.c
+++ b/contrib/debug/flags.c
@@ -180,7 +180,6 @@
 		printf("0\n");
 		return;
 	}
-	SHOW_FLAG(f, CS_FL_READ_PARTIAL);
 	SHOW_FLAG(f, CS_FL_NOT_FIRST);
 	SHOW_FLAG(f, CS_FL_KILL_CONN);
 	SHOW_FLAG(f, CS_FL_WAIT_FOR_HS);
diff --git a/include/haproxy/connection-t.h b/include/haproxy/connection-t.h
index c79f850..4b1a21d 100644
--- a/include/haproxy/connection-t.h
+++ b/include/haproxy/connection-t.h
@@ -81,7 +81,6 @@
 	 * the stream-interface :
 	 */
 	CS_FL_NOT_FIRST     = 0x00100000,  /* this stream is not the first one */
-	CS_FL_READ_PARTIAL  = 0x00200000,  /* some data were received (not necessarily xferred) */
 };
 
 /* cs_shutr() modes */
diff --git a/src/stream_interface.c b/src/stream_interface.c
index a6be2c9..45bcea3 100644
--- a/src/stream_interface.c
+++ b/src/stream_interface.c
@@ -1346,12 +1346,6 @@
 		if (cs->flags & CS_FL_WANT_ROOM)
 			si_rx_room_blk(si);
 
-		if (cs->flags & CS_FL_READ_PARTIAL) {
-			if (tick_isset(ic->rex))
-				ic->rex = tick_add_ifset(now_ms, ic->rto);
-			cs->flags &= ~CS_FL_READ_PARTIAL;
-		}
-
 		if (ret <= 0) {
 			/* if we refrained from reading because we asked for a
 			 * flush to satisfy rcv_pipe(), we must not subscribe