crypto: ice: Sanitize the ice device return address.

Even if ICE device is not found it is possible
for list device API to return non NULL pointer
which will pass all NULL checks in code. Ensure
to return proper address or NULL.

Change-Id: Ia6adf0587354c7d352c9e8d681de9d85fe5f1b98
Signed-off-by: ramandeep trehan <rtrehan@qti.qualcomm.com>