drm/i915/ttm: Fix error code in i915_ttm_eviction_valuable()

This function returns a bool type so returning -EBUSY is equivalent to
returning true.  It should return false instead.

Fixes: 7ae03459 ("drm/i915/ttm: add tt shmem backend")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211122061438.GA2492@kili

drivers/gpu/drm/i915/gem/i915_gem_ttm.c

@@ -332,7 +332,7 @@ static bool i915_ttm_eviction_valuable(struct ttm_buffer_object *bo,
 	 * but we would like to avoid grabbing locks for no good reason.
 	 */
 	if (bo->ttm && bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL)
-		return -EBUSY;
+		return false;
 
 	/* Will do for now. Our pinned objects are still on TTM's LRU lists */
 	return i915_gem_object_evictable(obj);