BUG/MINOR: config: disable http-reuse on TCP proxies

Louis Chanouha reported an inappropriate warning when http-reuse is
present in a defaults section while a TCP proxy accidently inherits
it and finds a conflict with other options like the use of the PROXY
protocol. To fix this patch removes the http-reuse option for TCP
proxies.

This fix needs to be backported to 1.8, 1.7 and possibly 1.6.
diff --git a/src/cfgparse.c b/src/cfgparse.c
index 621af6c..7653536 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -8507,6 +8507,9 @@
 			}
 #endif
 
+			if ((curproxy->mode != PR_MODE_HTTP) && (curproxy->options & PR_O_REUSE_MASK) != PR_O_REUSE_NEVR)
+				curproxy->options &= ~PR_O_REUSE_MASK;
+
 			if ((curproxy->options & PR_O_REUSE_MASK) != PR_O_REUSE_NEVR) {
 				if ((curproxy->conn_src.opts & CO_SRC_TPROXY_MASK) == CO_SRC_TPROXY_CLI ||
 				    (curproxy->conn_src.opts & CO_SRC_TPROXY_MASK) == CO_SRC_TPROXY_CIP ||