[PATCH] drm/i915: fix outdated i915_vma_get_fence() references in kdoc

[Kexin Sun <kexinsun@smail.nju.edu.cn>]

The function i915_vma_get_fence() was merged into
i915_vma_pin_fence() by commit 3bd4073524fa ("drm/i915:
Consolidate get_fence with pin_fence").

Remove the stale sentence that tells callers to synchronize
fencing state by calling i915_vma_get_fence() first, and fix
the Returns description: i915_vma_pin_fence() returns int
(0 on success, negative error code on failure), not bool as
the old i915_vma_get_fence() did.

Assisted-by: unnamed:deepseek-v3.2 coccinelle
Signed-off-by: Kexin Sun <kexinsun@smail.nju.edu.cn>
---
 drivers/gpu/drm/i915/i915_vma.h | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index 8054047840aa..14ad66f8b398 100644
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -369,14 +369,13 @@ void i915_vma_unpin_iomap(struct i915_vma *vma);
  * @vma: vma to pin fencing for
  *
  * This pins the fencing state (whether tiled or untiled) to make sure the
- * vma (and its object) is ready to be used as a scanout target. Fencing
- * status must be synchronize first by calling i915_vma_get_fence():
+ * vma (and its object) is ready to be used as a scanout target.
  *
  * The resulting fence pin reference must be released again with
  * i915_vma_unpin_fence().
  *
  * Returns:
- * True if the vma has a fence, false otherwise.
+ * 0 on success, negative error code on failure.
  */
 int __must_check i915_vma_pin_fence(struct i915_vma *vma);
 void i915_vma_revoke_fence(struct i915_vma *vma);
-- 
2.25.1