unset next/branch when block is written out
unset next/branch when block is written out

makes the decompiler stop crashing due to the new assertion

mltframework/swfdec,freedesktop-unofficial-mirror/swfdec__swfdec,freedesktop-unofficial-mirror/swfdec__swfdec,freedesktop-unofficial-mirror/swfdec__swfdec,mltframework/swfdec