msm: vidc: Fix race condition in STOP command

When clients send ETB's to driver, driver may defer them due
to instance not being moved to START_DONE yet. But the Stop
command may send ETB directly to HW without instance moving
to START_DONE. This results in unknown behavior from HW.
Hence before sending EOS ETB to HW, check the state. If not
reached right state, defer it same as ETB. Send these pending
EOS buffers when inst moved to START_DONE after sending pending
ETB's.

CRs-Fixed: 2095440
Change-Id: I510373ee8b13a13d8841171fd074b161ca8f5fd4
Signed-off-by: Praneeth Paladugu <ppaladug@codeaurora.org>