ijkplayer: convert pointer to string instead of using av_dict_set_int 

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CANTALOUPE (based on FFmpeg n3.3) 

GUAVA (based on FFmpeg n3.3) 

GRAPE (based on FFmpeg n3.3) 

PINEAPPLE 

CHERRY (based on FFmpeg n3.3) 

Pitaya (based on FFmpeg n3.2) 

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MANGA (based on FFmpeg n3.2)