drm/i915/selftests: Remove unused local variable 'file'

drivers/gpu/drm/i915/gem/selftests/i915_gem_object_blt.c:453 igt_threaded_blt() error: uninitialized symbol 'file'.

Fixes: 34485832 ("drm/i915/selftests: Exercise parallel blit operations on a single ctx")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191112163643.3527-1-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/gem/selftests/i915_gem_object_blt.c

@@ -435,7 +435,6 @@ static int igt_threaded_blt(struct drm_i915_private *i915,
 	struct task_struct **tsk;
 	unsigned int n_cpus, i;
 	I915_RND_STATE(prng);
-	struct file *file;
 	int err = 0;
 
 	n_cpus = num_online_cpus() + 1;
@@ -450,7 +449,7 @@ static int igt_threaded_blt(struct drm_i915_private *i915,
 
 	thread[0].file = mock_file(i915);
 	if (IS_ERR(thread[0].file)) {
-		err = PTR_ERR(file);
+		err = PTR_ERR(thread[0].file);
 		goto out_thread;
 	}