linux-phytec-fsl

drm/amdkfd: validate pdd where it acquired first

Currently pdd is validate after dereferencing it, which is
not correct, Thus validate pdd before its first use.

Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>