Sample - Added missing header (#336)

[ROCm/rocdecode commit: e2b9e7197a]

projects/rocdecode/samples/videoDecodeRGB/videodecrgb.cpp

@@ -21,6 +21,7 @@ THE SOFTWARE.
 */
 
 #include <iostream>
+#include <iomanip>
 #include <fstream>
 #include <unistd.h>
 #include <vector>