drm/vc4: allocate enough memory in vc4_save_hang_state()

"state" is smaller than "kernel_state" so we end up corrupting memory.

Fixes: 21461365 ('drm/vc4: Add an interface for capturing the GPU state after a hang.')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NEric Anholt <eric@anholt.net>

drivers/gpu/drm/vc4/vc4_gem.c

@@ -145,7 +145,7 @@ vc4_save_hang_state(struct drm_device *dev)
 	unsigned long irqflags;
 	unsigned int i, unref_list_count;
 
-	kernel_state = kcalloc(1, sizeof(*state), GFP_KERNEL);
+	kernel_state = kcalloc(1, sizeof(*kernel_state), GFP_KERNEL);
 	if (!kernel_state)
 		return;