drm/i915: remove unused i915_gem_lmem_obj_ops declaration

i915_gem_lmem_obj_ops has been removed since
commit 213d5092 ("drm/i915/ttm: Introduce a TTM i915
gem object backend"), so remove it.
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220913024847.552254-7-cuigaosheng1@huawei.com

drivers/gpu/drm/i915/gem/i915_gem_lmem.h

@@ -12,8 +12,6 @@ struct drm_i915_private;
 struct drm_i915_gem_object;
 struct intel_memory_region;
 
-extern const struct drm_i915_gem_object_ops i915_gem_lmem_obj_ops;
-
 void __iomem *
 i915_gem_object_lmem_io_map(struct drm_i915_gem_object *obj,
 			    unsigned long n,