Minor fix: added missing return value assignment

Author: AndreyPavlenko

lib/gc/ExecutionEngine/GPURuntime/ocl/GpuOclRuntime.cpp

@@ -218,8 +218,8 @@ struct OclRuntime::Exports {
     CL_CHECKR(err, "Failed to create OpenCL program with IL.");
 
     gcLogD("Created new OpenCL program: ", program);
-    clBuildProgram(program, 1, &ctx->runtime.ext.device, nullptr, nullptr,
-                   nullptr);
+    err = clBuildProgram(program, 1, &ctx->runtime.ext.device, nullptr, nullptr,
+                         nullptr);
     CL_CHECKR(err, "Failed to build the program: ", program);
     gcLogD("The program has been built: ", program);