Fix poc for field pictures. Prior to this, the poc of the second field  in decoding order would always be assigned to a field pair's poc.
Fix poc for field pictures. Prior to this, the poc of the second field 
in decoding order would always be assigned to a field pair's poc.

Original thread: H.264: Fix poc for field pairs, 6 Nov 2007 17:41:02



git-svn-id: a4d7c1866f8397a4106e0b57fc4fbf792bbdaaaf@10937 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

prajnashi/ffmpeg,prajnashi/ffmpeg,prajnashi/ffmpeg,prajnashi/ffmpeg