Added first half of ROI support (#41)

* Finished first half of adding ROI functionality to rocJPEG

* took out unnecessary .h file

* addressed review comments from Aryan

* fixed typo

* fixed documentation in code for decode_params

* fixed the spaces

[ROCm/rocjpeg commit: 6ce373b2a1]

projects/rocjpeg/samples/jpegDecode/jpegdecode.cpp

@@ -100,7 +100,7 @@ int main(int argc, char **argv) {
                 return EXIT_FAILURE;
         }
 
-        if (rocjpeg_utils.GetChannelPitchAndSizes(decode_params.output_format, subsampling, widths, heights, num_channels, output_image, channel_sizes)) {
+        if (rocjpeg_utils.GetChannelPitchAndSizes(decode_params, subsampling, widths, heights, num_channels, output_image, channel_sizes)) {
             std::cerr << "ERROR: Failed to get the channel pitch and sizes" << std::endl;
             return EXIT_FAILURE;
         }