[Intel-gfx] [PATCH i-g-t] lib: Fix igt_sysfs_set_u32 return value

[Chris Wilson]

Quoting Tvrtko Ursulin (2017-09-29 12:29:49)
> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> 
> Printf family functions return a number of bytes, not tokens,
> printed so the existing check (== 1) was wrong.

Oops, copied from scanf without thinking.
 
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
-Chris