added cpu performance test for gpu module

modules/gpu/perf_cpu/perf_objdetect.cpp

@@ -0,0 +1,27 @@
+#include "perf_precomp.hpp"
+
+#ifdef HAVE_CUDA
+
+GPU_PERF_TEST_1(HOG, cv::gpu::DeviceInfo)
+{
+    cv::gpu::DeviceInfo devInfo = GetParam();
+
+    cv::gpu::setDevice(devInfo.deviceID());
+
+    cv::Mat img_host = readImage("gpu/hog/road.png", cv::IMREAD_GRAYSCALE);
+
+    cv::gpu::GpuMat img(img_host);
+    std::vector<cv::Rect> found_locations;
+
+    cv::gpu::HOGDescriptor hog;
+    hog.setSVMDetector(cv::gpu::HOGDescriptor::getDefaultPeopleDetector());
+
+    TEST_CYCLE()
+    {
+        hog.detectMultiScale(img, found_locations);
+    }
+}
+
+INSTANTIATE_TEST_CASE_P(ObjDetect, HOG, ALL_DEVICES);
+
+#endif