drm/i915: Squelch any ktime/jiffie rounding errors for wait-ioctl

drm/i915: Squelch any ktime/jiffie rounding errors for wait-ioctl

We wait upon jiffies, but report the time elapsed using a
high-resolution timer. This discrepancy can lead to us timing out the
wait prior to us reporting the elapsed time as complete.

This restores the squelching lost in commit e95433c73a11 ("drm/i915:
Rearrange i915_wait_request() accounting with callers").

Fixes: e95433c73a11 ("drm/i915: Rearrange i915_wait_request() accounting with callers")
Signed-off-by: Chris Wilson <[email protected]>
Cc: Matthew Auld <[email protected]>
Cc: Joonas Lahtinen <[email protected]>
Cc: <[email protected]> # v4.10-rc1+
Cc: [email protected]
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
Reviewed-by: Joonas Lahtinen <[email protected]>