CMake: detect the XInclude feature in libxml2
CMake: detect the XInclude feature in libxml2

xmlserializer needs the XInclude feature (its usage in structure files is
optional but xmlserializer needs the symbols for compiling).

Verbosely fail if libxml2 has not been configured with XInclude support.

Signed-off-by: David Wagner <60228a510f9a76940848fa2d29321fc4edfc2119@intel.com>

mgaio/parameter-framework,clero/parameter-framework,sdnnfv/parameter-framework,krocard/parameter-framework,tcahuzax/parameter-framework,pafonso/parameter-framework,zchokri/parameter-framework,01org/parameter-framework,krocard/parameter-framework,tcahuzax/parameter-framework,dbrageul/parameter-framework,pafonso/parameter-framework,clero/parameter-framework,tcahuzax/parameter-framework,sdnnfv/parameter-framework,mgaio/parameter-framework,anwarMov/parameter-framework,soaresm/parameter-framework,01org/parameter-framework,anwarMov/parameter-framework,anwarMov/parameter-framework,pafonso/parameter-framework,wzairix/parameter-framework,android-ia/hardware_intel_parameter-framework,miguelgaio/parameter-framework,dbrageul/parameter-framework,geekboxzone/mmallow_external_parameter-framework,zchokri/parameter-framework,Makohoek/parameter-framework,android-ia/hardware_intel_parameter-framework,android-ia/hardware_intel_parameter-framework,geekboxzone/mmallow_external_parameter-framework,dbrageul/parameter-framework,Makohoek/parameter-framework,soaresm/parameter-framework,miguelgaio/parameter-framework,dawagner/parameter-framework,wzairix/parameter-framework,wzairix/parameter-framework,miguelgaio/parameter-framework,01org/parameter-framework,zchokri/parameter-framework,geekboxzone/mmallow_external_parameter-framework,Makohoek/parameter-framework,dawagner/parameter-framework,krocard/parameter-framework,soaresm/parameter-framework,dawagner/parameter-framework,mgaio/parameter-framework,AdrienMQ/parameter-framework,clero/parameter-framework,sdnnfv/parameter-framework,AdrienMQ/parameter-framework,AdrienMQ/parameter-framework