commit dfee4111 upstream.

Fix NULL pointer exception when platform data is not supplied. The
driver dereferenced pdata pointer where it could be NULL.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Fixes: 810d601fSigned-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>