fix FTBFS, c++ linking needs -lstdc++ explicitly
https://bugzilla.redhat.com/show_bug.cgi?id=631288
-diff -up apcupsd-3.14.8/src/Makefile.cxxld apcupsd-3.14.8/src/Makefile
---- apcupsd-3.14.8/src/Makefile.cxxld 2009-09-30 01:20:45.000000000 +0200
-+++ apcupsd-3.14.8/src/Makefile 2010-09-22 11:18:03.550601657 +0200
-@@ -26,10 +26,10 @@ SRCS = $(common_srcs) $(apcupsd_srcs) $(
- all-targets: apcupsd apcaccess apctest smtp
+--- apcupsd-3.14.13/src/Makefile~ 2014-11-04 21:17:43.000000000 +0200
++++ apcupsd-3.14.13/src/Makefile 2015-09-16 16:42:11.150220917 +0300
+@@ -30,10 +30,10 @@
+ all-targets: apcupsd$(EXE) apcaccess$(EXE) apctest$(EXE) smtp$(EXE)
- apcupsd: $(common_obj) $(apcupsd_obj) $(APCDRVLIBS) $(APCLIBS)
-- $(LINK) $(DRVLIBS)
-+ $(LINK) -lstdc++ $(DRVLIBS)
+ apcupsd$(EXE): $(common_obj) $(apcupsd_obj) $(APCDRVLIBS) $(APCLIBS)
+- $(LINK) $(DRVLIBS) $(BG)
++ $(LINK) -lstdc++ $(DRVLIBS) $(BG)
- apctest: $(common_obj) $(apctest_obj) $(APCDRVLIBS) $(APCLIBS)
+ apctest$(EXE): $(common_obj) $(apctest_obj) $(APCDRVLIBS) $(APCLIBS)
- $(LINK) $(DRVLIBS)
+ $(LINK) -lstdc++ $(DRVLIBS)
- apcaccess: $(apcaccess_obj) $(APCLIBS)
+ apcaccess$(EXE): $(apcaccess_obj) $(APCLIBS)
$(LINK)