Revert "drm/ttm: fix memleak in ttm_transfered_destroy"

Revert "drm/ttm: fix memleak in ttm_transfered_destroy"

This reverts commit c21b4002214c1c7e7b627b9b53375612f7aab6db which is
commit 0db55f9a1bafbe3dac750ea669de9134922389b5 upstream.

Seems that the older kernels can not handle this fix because, to quote
Christian:
	The problem is this memory leak could potentially happen with
	5.10 as wel, just much much much less likely.

	But my guess is that 5.10 is so buggy that when the leak does
	NOT happen we double free and obviously causing a crash.

So it needs to be reverted.

Link: https://lore.kernel.org/r/1a1cc125-9314-f569-a6c4-40fc4509a377@amd.com
Cc: Christian König <christian.koenig@amd.com>
Cc: Erhard F. <erhard_f@mailbox.org>
Cc: Erhard F. <erhard_f@mailbox.org>
Cc: Huang Rui <ray.huang@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>