media: chips-media: wave5: Release m2m_ctx after Instance Removed from List

media: chips-media: wave5: Release m2m_ctx after Instance Removed from List

Possible use after free if IRQ thread manages to obtain spinlock between
m2m_ctx release and wave5_release function removing stream instance from
list of active instances. The IRQ thread looks for the m2m_ctx which is
freed so null pointer dereference occurs.

Signed-off-by: Brandon Brnich <b-brnich@ti.com>
Reviewed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Tested-by: Jackson Lee <jackson.lee@chipsnmedia.com>
Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>