ffplay: signal the frame queue before closing audio

Fixed regression caused by 631ac655c00e978e19d05dab572bc1ffd6078c63 when ffplay
does not quit if the audio thread is blocked.

Signed-off-by: Marton Balint <cus@passwd.hu>
Merge remote-tracking branch 'cus/stable'

* cus/stable:
  ffplay: signal the frame queue before closing audio

Merged-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/h264_parser: Avoid adding SEI to the global header

Only consider SEI when no PPS has been found yet

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>