The tee_shm_get_va() function never returns NULL, it returns error
pointers. Update the check to match.
Fixes: f0c8431568 ("optee: probe RPMB device using RPMB subsystem")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Link: https://lore.kernel.org/r/f8c12aed-b5d1-4522-bf95-622b8569706d@stanley.mountain
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>