drm/virtio: release the GEM object on virtio_gpu_vram_create() errors

In the Linux kernel, the following vulnerability has been resolved: drm/virtio: release the GEM object on virtio_gpu_vram_create() errors virtio_gpu_vram_create() frees the object with a bare kfree(vram) on both error paths after drm_gem_private_object_init() has run, and on the second one after drm_gem_create_mmap_offset() has linked obj->vma_node into the device's VMA offset manager. The freed object stays in that interval tree, so a later lookup or insertion walks freed memory, and the dma_resv and gpuva lock are never destroyed. Call drm_gem_object_release() before kfree() on both paths.

Where it's fixed