libxmlrpc: fix build without C++ compiler

Conditionally disable compilation of optional C++ module.

Fixes:

  http://autobuild.buildroot.net/results/cbff6c816606a515467d467677763533a41fc276/

Signed-off-by: Alvaro Gamez Machado <alvaro.gamez@hazent.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/libxmlrpc/0002-fix-non-cplusplus-build.patch

@@ -1,9 +1,10 @@
 Handle builds without C++
 
 libxmlrpc nicely handles the fact of being built without C++ support,
-except for one location, fixed by this patch.
+except for two locations, fixed by this patch.
 
 Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+Signed-off-by: Alvaro Gamez Machado <alvaro.gamez@hazent.com>
 
 Index: b/lib/util/Makefile
 ===================================================================
@@ -25,3 +26,19 @@ Index: b/lib/util/Makefile
  .PHONY: all
  all: $(LIBOBJS)
  
+Index: b/lib/Makefile
+===================================================================
+--- a/lib/Makefile
++++ b/lib/Makefile
+@@ -9,7 +9,10 @@
+ 
+ # Build up SUBDIRS:
+ SUBDIRS = 
+-SUBDIRS += util libutil libutil++
++SUBDIRS += util libutil
++ifeq ($(ENABLE_CPLUSPLUS),yes)
++  SUBDIRS += libutil++
++endif
+ ifeq ($(ENABLE_ABYSS_SERVER),yes)
+   SUBDIRS += abyss
+   ifeq ($(ENABLE_CPLUSPLUS),yes)