BUG/MINOR: proxy: don't dump servers of internal proxies

Patch 211c967 ("MINOR: httpclient: add the server to the proxy") broke
the reg-tests that do a "show servers state".

Indeed the servers of the proxies flagged with PR_CAP_INT are dumped in
the output of this CLI command.

This patch fixes the issue par ignoring the PR_CA_INT proxies in the
dump.
diff --git a/src/proxy.c b/src/proxy.c
index 3391dc9..2642b44 100644
--- a/src/proxy.c
+++ b/src/proxy.c
@@ -2577,7 +2577,7 @@
 	for (; appctx->ctx.cli.p0 != NULL; appctx->ctx.cli.p0 = curproxy->next) {
 		curproxy = appctx->ctx.cli.p0;
 		/* servers are only in backends */
-		if (curproxy->cap & PR_CAP_BE) {
+		if ((curproxy->cap & PR_CAP_BE) && !(curproxy->cap & PR_CAP_INT)) {
 			if (!dump_servers_state(si))
 				return 0;
 		}