[PATCH xserver] Convert server to masked input valuators

[Jesse Adkins]

>+    if (type == MotionNotify &&
>+        CountBits(mask->mask, mask->len) <= 0)
Should be == 0. CountBits doesn't return negative values.

>+    InjectPointerKeyEvents(dev, MotionNotify, 0, gpe_flags, &mask, (int[]){x, y});
That's a C99 cast there. It shouldn't have been like that in the first place.
I was told that X is supposed to work on C89 when I tried to add a
__FUNCTION__ to __func__ patch a while back.

Out of curiosity, why are CountBits and ValuatorRangeToMask being exported?