msm: vidc: Set ETB extradata address to NULL during EOS

Firmware needs to access extradata buffer to find the size of extradata.
In secure sessions, assigning input buffer address to extradata address
causes fault since firmware does not have access to input adderss.
Extradata address and size in ETB must be set to zero for EOS cases
so that firmware skips accessing the extradata buffer.

CRs-Fixed: 2444064
Change-Id: Ia916d2f5f0500c85426fee3274f88fcf36103068
Signed-off-by: Mihir Ganu <mganu@codeaurora.org>