FROMGIT: media: venus: Add a check for packet size after reading from shared memory

Add a check to ensure that the packet size does not exceed the number of
available words after reading the packet header from shared memory. This
ensures that the size provided by the firmware is safe to process and
prevent potential out-of-bounds memory access.

Signed-off-by: Vedang Nagar <quic_vnagar@quicinc.com>
Co-developed-by: Dikshita Agarwal <quic_dikshita@quicinc.com>
Signed-off-by: Dikshita Agarwal <quic_dikshita@quicinc.com>
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Bryan O'Donoghue <bod@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>

(cherry picked from commit 49befc83 https://gitlab.freedesktop.org/linux-media/media-committers.git

 master)
Change-Id: I6d0e34681bfaec467879c0dd34b74e50b7879822
Signed-off-by: Gaviraju Doddabettahalli Bettegowda <quic_gdoddabe@quicinc.com>