memory: Small changes to fix some memory leaks.

Four small leaks in *scam, sx1276, and ozw.  Added calls to
cleanup resources before throws.

Signed-off-by: Noel Eck <noel.eck@intel.com>

src/grovescam/grovescam.cxx

@@ -468,6 +468,7 @@ bool GROVESCAM::storeImage(const char *fname)
             goto retry;
           else
             {
+              fclose(file);
               throw std::runtime_error(std::string(__FUNCTION__) +
                                        ": cksum error, maximum retries exceeded");
               return false;