[network-manager-pptp] build: really fix linking against libdl.so for dlopen()

[Thomas Haller <thaller src gnome org>]

commit 6b4e2c1d268afd69208864971c0ec45ef35486d1
Author: Thomas Haller <thaller redhat com>
Date:   Wed Sep 7 18:59:33 2016 +0200

    build: really fix linking against libdl.so for dlopen()
    
    Fixes: f3e916714196d7687bb8920a9d0339f7fe4bbf7c

 properties/Makefile.am |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/properties/Makefile.am b/properties/Makefile.am
index 1a3e750..7cc4739 100644
--- a/properties/Makefile.am
+++ b/properties/Makefile.am
@@ -46,7 +46,7 @@ libnm_vpn_plugin_pptp_la_CFLAGS = \
 
 libnm_vpn_plugin_pptp_la_LIBADD = \
     $(LIBNM_LIBS) \
-    $(LD_LIBS) \
+    $(DL_LIBS) \
     $(NULL)
 
 libnm_vpn_plugin_pptp_la_LDFLAGS = \