player: don't reset buffering pausing state on seeks

This was added with commit 3cbd79b3, but it turns out this
unintentionally enables "real" pausing when seeking while buffering. It
was done for ensuring correct state of the "cache-buffering-state"
property, but it also turns out that this was unneeded (another variable
that is reset when seeking happens to take care of this).

player/playloop.c

@@ -155,7 +155,6 @@ void reset_playback_state(struct MPContext *mpctx)
     mpctx->last_seek_pts = MP_NOPTS_VALUE;
     mpctx->cache_wait_time = 0;
     mpctx->restart_complete = false;
-    mpctx->paused_for_cache = false;
 
 #if HAVE_ENCODING
     encode_lavc_discontinuity(mpctx->encode_lavc_ctx);