drm/msm/hdmi: Simplify with local 'dev' variable

drm/msm/hdmi: Simplify with local 'dev' variable

msm_hdmi_dev_probe() function already stores pdev->dev in local
variable, so use it directly to make code simpler.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/711171/
Link: https://lore.kernel.org/r/20260311-drm-msm-hdmi-cleanup-v1-3-c5535245f6de@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>