added performance tests for gpu module

modules/gpu/perf/perf_main.cpp

@@ -0,0 +1,22 @@
+#include "perf_precomp.hpp"
+
+#ifdef HAVE_CUDA
+
+int main(int argc, char **argv)
+{
+    testing::InitGoogleTest(&argc, argv);
+    cvtest::TS::ptr()->init("gpu");
+    Regression::Init("gpu");
+    TestBase::Init(argc, argv);
+    return RUN_ALL_TESTS();
+}
+
+#else
+
+int main(int argc, char** argv)
+{
+    printf("OpenCV was built without CUDA support\n");
+    return 0;
+}
+
+#endif