Revert "media: vimc: skip .s_stream() for stopped entities"

This reverts commit a5050757 which is
commit 36cef585 upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: Ia3bf677ea97e0fc92cec646b59246e8cbc5eb5ce
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>