Fixes:
h264.h: In function 'fill_filter_caches':
h264.h:1216:73: warning: integer overflow in expression
h264.h:1307:81: warning: integer overflow in expression


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@21813 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b