REORG: include: move common/net_helper.h to haproxy/net_helper.h

No change was necessary.
diff --git a/src/dns.c b/src/dns.c
index 73258c0..20ccc6d 100644
--- a/src/dns.c
+++ b/src/dns.c
@@ -24,7 +24,7 @@
 #include <haproxy/errors.h>
 #include <haproxy/time.h>
 #include <common/ticks.h>
-#include <common/net_helper.h>
+#include <haproxy/net_helper.h>
 
 #include <types/action.h>
 #include <types/applet.h>