staging: sbe-2t3e3: fix error handling in t3e3_init_channel()

t3e3_init_channel() incorrectly handles errors in several places:
it returns zero and does not deallocate all required resources.
The patch fixes that places.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>