fix(ffmpeg): add native filesystem API support for FFmpeg image decoder (#7253)

lv_conf_template.h

@@ -932,6 +932,10 @@
 #if LV_USE_FFMPEG
     /** Dump input information to stderr */
     #define LV_FFMPEG_DUMP_FORMAT 0
+    /** Use lvgl file path in FFmpeg Player widget 
+     *  You won't be able to open URLs after enabling this feature.
+     *  Note that FFmpeg image decoder will always use lvgl file system. */
+    #define LV_FFMPEG_PLAYER_USE_LV_FS 0
 #endif
 
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