HDLCD crashes with 6d910bfa809e

Hi Daniel, Liviu,

Having just inadvertently merged -next into my working branch, I find 
dev6d910bfa809e ("drm/hlcd: Use lockless gem BO free callback") 
adversely affecting my board's ability to boot ;)

Since I (intentionally) don't have sufficient CMA to create a 
framebuffer, drm_gem_cma_create() fails, unconditionally calls the 
now-NULL drm->driver->gem_free_object() in its cleanup path, and fiery 
death ensues...

Regards,
Robin.