process_pipeline: fix memleak in save_jpeg

```
==70481== 7,680 bytes in 2 blocks are definitely lost in loss record 64,498 of 64,727
==70481==    at 0x4844818: malloc (vg_replace_malloc.c:446)
==70481==    by 0x11EDA5: save_jpeg (process_pipeline.c:1016)
==70481==    by 0x11F090: process_image_for_capture_yuv (process_pipeline.c:1078)
==70481==    by 0x11F5BC: process_image_for_capture (process_pipeline.c:1249)
==70481==    by 0x11FAB3: process_image (process_pipeline.c:1393)
```

src/process_pipeline.c

@@ -1067,6 +1067,7 @@ save_jpeg(const uint8_t *image, char *fname)
         jpeg_finish_compress(&cinfo);
         fclose(outfile);
         jpeg_destroy_compress(&cinfo);
+	free(row);
 }
 
 static void