Fix missing initialization of deinterlace intermediate buffer

When color format is other than 420p, deinterlacer uses intermediate
buffer for storing chroma output.
For multi-threaded cases, this intermediate buffer was not initialized
in all thread contexts.

Bug: 136697219
Test: poc in bug
Change-Id: I45d4e7634ed0e2c126a5508aea011617b6c6cc25
(cherry picked from commit 5e15457fadb59bfc75077ef9e2592f835185a32b)