drm/i915: Fix rsvd2 mask when out-fence is returned

drm/i915: Fix rsvd2 mask when out-fence is returned

GENMASK_ULL wants the high bit of the mask first. The current value
cancels the in-fence when an out-fence is returned.

Fixes: fec0445caa273 ("drm/i915: Support explicit fencing for execbuf")
Testcase: igt/gem_exec_fence/keep-in-fence*
Cc: Chris Wilson <[email protected]>
Signed-off-by: Daniele Ceraolo Spurio <[email protected]>
Reviewed-by: Chris Wilson <[email protected]>
Signed-off-by: Chris Wilson <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
Cc: <[email protected]> # v4.12+
(cherry picked from commit b6a88e4a804cf5a71159906e16df2c1fc7196f92)
Signed-off-by: Rodrigo Vivi <[email protected]>