Is it possible to use Xilinx FPGA with Intel FPGA SDK for OpenCL ?

Doubt it! Intel's implementation only supports a subset of its own board, so its highly unlikely that it would support Xilinx as its a competitor! Did you try SDAccel which is the equivalent product for Xilinx? See http://www.xilinx.com/products/design-tools/software-zone/sdaccel.html