drm/i915: don't leak lmem mapping in vma_evict

Don't leak lmem mapping in vma_evict, move __i915_vma_iounmap outside
i915_vma_is_map_and_fenceable.

Signed-off-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.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/20220610121205.29645-3-juhapekka.heikkila@gmail.com

drivers/gpu/drm/i915/i915_vma.c

@@ -1907,9 +1907,11 @@ struct dma_fence *__i915_vma_evict(struct i915_vma *vma, bool async)
 		/* release the fence reg _after_ flushing */
 		i915_vma_revoke_fence(vma);
 
-		__i915_vma_iounmap(vma);
 		clear_bit(I915_VMA_CAN_FENCE_BIT, __i915_vma_flags(vma));
 	}
+
+	__i915_vma_iounmap(vma);
+
 	GEM_BUG_ON(vma->fence);
 	GEM_BUG_ON(i915_vma_has_userfault(vma));