BUG/MINOR: config: don't inherit the default balance algorithm in frontends

Tom Limoncelli from Stack Exchange reported a minor bug : the frontend
inherits the LB parameters from the defaults sections. The impact is
that if a "balance" directive uses any L7 parameter in the defaults
sections and the frontend is in TCP mode, a warning is emitted about
their incompatibility. The warning is harmless but a valid, sane config
should never cause any warning to be reported.

This fix should be backported into 1.5 and possibly 1.4.
(cherry picked from commit 743c128580ee29c8f073b4a29771a5ce715f3721)
diff --git a/src/cfgparse.c b/src/cfgparse.c
index 392a692..40d20ab 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -2003,7 +2003,6 @@
 		curproxy->no_options = defproxy.no_options;
 		curproxy->no_options2 = defproxy.no_options2;
 		curproxy->bind_proc = defproxy.bind_proc;
-		curproxy->lbprm.algo = defproxy.lbprm.algo;
 		curproxy->except_net = defproxy.except_net;
 		curproxy->except_mask = defproxy.except_mask;
 		curproxy->except_to = defproxy.except_to;
@@ -2037,6 +2036,7 @@
 		}
 
 		if (curproxy->cap & PR_CAP_BE) {
+			curproxy->lbprm.algo = defproxy.lbprm.algo;
 			curproxy->fullconn = defproxy.fullconn;
 			curproxy->conn_retries = defproxy.conn_retries;
 			curproxy->max_ka_queue = defproxy.max_ka_queue;