xwayland: Damage surface in surface-relative coordinates

In 9141196d positional coordinates were added to the damage call of pixmap
flips. The damage box coordinates are in screen space though and we need
to convert them first to surface-relative ones by substracting the origin
of the window.

Signed-off-by: Roman Gilg <subdiff@gmail.com>
4 jobs for present-damage-fix in 4 minutes and 27 seconds (queued for 1 second)
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debian-testing

00:00:18

 
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autotools

00:04:08

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meson

00:01:31

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meson-noglamor

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