drm/i915: Exercise i915_vma_pin/i915_vma_insert

High-level testing of the struct drm_mm by verifying our handling of
weird requests to i915_vma_pin.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170213171558.20942-35-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index e6c565f..0dc994b 100644
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -327,8 +327,8 @@ void i915_vma_unpin_and_release(struct i915_vma **p_vma)
 	__i915_gem_object_release_unless_active(obj);
 }
 
-bool
-i915_vma_misplaced(struct i915_vma *vma, u64 size, u64 alignment, u64 flags)
+bool i915_vma_misplaced(const struct i915_vma *vma,
+			u64 size, u64 alignment, u64 flags)
 {
 	if (!drm_mm_node_allocated(&vma->node))
 		return false;