Another fix from FXE test that I missed

src/calng/kernels/peakfinder9_gpu.cu

@@ -161,7 +161,7 @@ extern "C" __global__ void pf9(const unsigned short num_frames,
 		float peak_weighted_fs_nom = 0;
 		// expand peak in rings
 		const float peak_pixel_threshold = mean + min_snr_peak_pixels * sigma;
-		for (unsigned short layer=1; layer<=window_radius; ++layer) {
+		for (unsigned short layer=0; layer<=window_radius; ++layer) {
 			unsigned num_peak_pixels_before = num_peak_pixels;
 			masked_frame.fun_ring(ss_index, fs_index, layer, [&] (unsigned short i, unsigned short j, float val) {
 				if (val > peak_pixel_threshold) {