buildsys: Move vde libs to per object

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170907083552.17725-3-famz@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>

configure

@@ -2946,8 +2946,6 @@ int main(void)
 EOF
   if compile_prog "" "$vde_libs" ; then
     vde=yes
-    libs_softmmu="$vde_libs $libs_softmmu"
-    libs_tools="$vde_libs $libs_tools"
   else
     if test "$vde" = "yes" ; then
       feature_not_found "vde" "Install vde (Virtual Distributed Ethernet) devel"
@@ -5499,6 +5497,7 @@ if test "$slirp" = "yes" ; then
 fi
 if test "$vde" = "yes" ; then
   echo "CONFIG_VDE=y" >> $config_host_mak
+  echo "VDE_LIBS=$vde_libs" >> $config_host_mak
 fi
 if test "$netmap" = "yes" ; then
   echo "CONFIG_NETMAP=y" >> $config_host_mak

net/Makefile.objs

@@ -21,3 +21,5 @@ tap-obj-$(CONFIG_SOLARIS) = tap-solaris.o
 tap-obj-y ?= tap-stub.o
 common-obj-$(CONFIG_POSIX) += tap.o $(tap-obj-y)
 common-obj-$(CONFIG_WIN32) += tap-win32.o
+
+vde.o-libs = $(VDE_LIBS)