VIDEO: Mark Smacker _frameTypes as protected

It's used by the Nightlong Smacker decoder when seeking to a frame

video/smk_decoder.h

@@ -195,6 +195,7 @@ private:
 		bool seek(const Audio::Timestamp &time) { return true; }
 	};
 
+protected:
 	// The FrameTypes section of a Smacker file contains an array of bytes, where
 	// the 8 bits of each byte describe the contents of the corresponding frame.
 	// The highest 7 bits correspond to audio frames (bit 7 is track 6, bit 6 track 5
@@ -202,6 +203,7 @@ private:
 	// (bit 0) is set, it denotes a frame that contains a palette record
 	byte *_frameTypes;
 
+private:
 	uint32 _firstFrameStart;
 };