dma-buf: dma_fence_wait must enable signaling

dma_fence_wait() should always enable signaling even
when the fence is already signaled.

Signed-off-by: Arvind Yadav <Arvind.Yadav@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220914164321.2156-5-Arvind.Yadav@amd.com
Signed-off-by: Christian König <christian.koenig@amd.com>