movieinfo: remove obsolete miSource source

Origin commit data
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Branch: ni/coolstream
Commit: 3ab8212d4c
Author: vanhofen <vanhofen@gmx.de>
Date: 2022-11-27 (Sun, 27 Nov 2022)

Origin message was:
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- movieinfo: remove obsolete miSource source

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No further description and justification available within origin commit message!

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This commit was generated by Migit

src/driver/movieinfo.cpp

@@ -576,7 +576,6 @@ void MI_MOVIE_INFO::clear(void)
 
 	marked = false;
 	delAsk = true;
-	source = UNKNOWN;
 }
 
 bool CMovieInfo::loadFile(CFile &file, std::string &buffer)

src/driver/movieinfo.h

@@ -149,12 +149,6 @@ class MI_MOVIE_INFO //MI_MOVIE_INFO &operator=(const MI_MOVIE_INFO& src);
 
 		std::string tfile;		// thumbnail/cover file name
 
-		enum miSource {
-			UNKNOWN = 0,
-			NK
-		};
-		miSource source;
-
 		void clear(void);
 		MI_MOVIE_INFO() { clear(); }
 };