player: do not exit when a seek gets queued

Seems logical.

Note that if playback otherwise ends while playback is active and a seek
is still queued, we still exit. Otherwise you couldn't end playback by
seeking past the end of the file (which is classic MPlayer and mpv
behavior).

player/playloop.c

@@ -303,6 +303,10 @@ void queue_seek(struct MPContext *mpctx, enum seek_type type, double amount,
                 enum seek_precision exact, bool immediate)
 {
     struct seek_params *seek = &mpctx->seek;
+
+    if (mpctx->stop_play == AT_END_OF_FILE)
+        mpctx->stop_play = KEEP_PLAYING;
+
     switch (type) {
     case MPSEEK_RELATIVE:
         seek->immediate |= immediate;