REORG: include: move http_fetch.h to haproxy/http_fetch.h

There's no type file for this trivial one. The unneeded dependency on
htx.h was dropped.
diff --git a/src/fcgi-app.c b/src/fcgi-app.c
index 10a8de5..68d0efe 100644
--- a/src/fcgi-app.c
+++ b/src/fcgi-app.c
@@ -14,6 +14,7 @@
 #include <haproxy/chunk.h>
 #include <common/cfgparse.h>
 #include <haproxy/errors.h>
+#include <haproxy/http_fetch.h>
 #include <haproxy/http_htx.h>
 #include <haproxy/regex.h>
 #include <haproxy/sample.h>
@@ -24,7 +25,6 @@
 #include <proto/acl.h>
 #include <proto/fcgi-app.h>
 #include <proto/filters.h>
-#include <proto/http_fetch.h>
 #include <proto/log.h>
 #include <proto/proxy.h>
 #include <proto/server.h>