fix(piopencl): release context on command queue creation failure

If clCreateContext succeeded but clCreateCommandQueue failed,
the context handle was returned without being released, leaking
the OpenCL context and all associated GPU resources.

libs/opencl/piopencl.cpp

@@ -213,6 +213,7 @@ PIOpenCL::Context * PIOpenCL::Context::create(const PIOpenCL::DeviceList & dl) {
 	if (ret != 0) {
 		piCout << "[PIOpenCL::Context]"
 			   << "clCreateCommandQueue error" << ret;
+		clReleaseContext(con);
 		return 0;
 	}
 	piCout << "create done for" << dl[0].name;