Fix typo in src/input/stream.c to use CAN_FASTSEEK instead of CAN_SEEK

There is a bug in AStreamSeekStream that is causing all input modules
that support CAN_SEEK to be treated as CAN_FASTSEEK.  This in turn
causes far too many seeks in slower seeking sources which results in
performance problems when playing video.  The fix is a simple change of
CAN_SEEK to CAN_FASTSEEK.
Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>
(cherry picked from commit ce127fd5)

src/input/stream.c

@@ -1149,7 +1149,7 @@ static int AStreamSeekStream( stream_t *s, int64_t i_pos )
     }
 
     bool   b_afastseek;
-    access_Control( p_access, ACCESS_CAN_SEEK, &b_afastseek );
+    access_Control( p_access, ACCESS_CAN_FASTSEEK, &b_afastseek );
 
     /* FIXME compute seek cost (instead of static 'stupid' value) */
     int64_t i_skip_threshold;