dma-buf/fence: add signal_on_any to the fence array v2

If @signal_on_any is true the fence array signals if any fence in the array
signals, otherwise it signals when all fences in the array signal.

v2: fix signaled test and add comment suggested by Chris Wilson.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1464786612-5010-4-git-send-email-deathsimple@vodafone.de