genesys: fix gcc-4.8 compile

Fixes:

  genesys/utilities.h:229:23: error: invalid initialization of non-const reference of type 'std::basic_ios<char>&' from an rvalue of type '<brace-enclosed initializer list>'
           stream_{stream}
                         ^
  genesys/image_pipeline.cpp:715:19: error: invalid initialization of non-const reference of type 'genesys::ImagePipelineNode&' from an rvalue of type '<brace-enclosed initializer list>'
       source_{source}
                     ^

Signed-off-by: Peter Seiderer <ps.report@gmx.net>

backend/genesys/image_pipeline.cpp

@@ -712,7 +712,7 @@ ImagePipelineNodeCalibrate::ImagePipelineNodeCalibrate(ImagePipelineNode& source
                                                        const std::vector<std::uint16_t>& bottom,
                                                        const std::vector<std::uint16_t>& top,
                                                        std::size_t x_start) :
-    source_{source}
+    source_(source)
 {
     std::size_t size = 0;
     if (bottom.size() >= x_start && top.size() >= x_start) {

backend/genesys/utilities.h

@@ -226,7 +226,7 @@ class BasicStreamStateSaver
 {
 public:
     explicit BasicStreamStateSaver(std::basic_ios<Char, Traits>& stream) :
-        stream_{stream}
+        stream_(stream)
     {
         flags_ = stream_.flags();
         width_ = stream_.width();