Revert "sub/sd_lavc: don't check endpts when getting subs"

This reverts commit 02a80f850b. Bad idea.
This causes subs to stay on the screen too long in some cases. Let's try
something else to fix the problem.

sub/sd_lavc.c

@@ -398,7 +398,8 @@ static struct sub *get_current(struct sd_lavc_priv *priv, double pts)
         if (!sub->valid)
             continue;
         if (pts == MP_NOPTS_VALUE ||
-            (sub->pts == MP_NOPTS_VALUE || pts + 1e-6 >= sub->pts))
+            ((sub->pts == MP_NOPTS_VALUE || pts + 1e-6 >= sub->pts) &&
+             (sub->endpts == MP_NOPTS_VALUE || pts < sub->endpts)))
         {
             // Ignore "trailing" subtitles with unknown length after 1 minute.
             if (sub->endpts == MP_NOPTS_VALUE && pts >= sub->pts + 60)