drm/amdgpu: fix ACA bank count boundary check error

fix ACA bank count boundary check error.

Fixes: f5e4cc8461c4 ("drm/amdgpu: implement RAS ACA driver framework")
Signed-off-by: Yang Wang <[e-mail]>
Reviewed-by: Tao Zhou <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/amdgpu/amdgpu_aca.c

···
 		return -EINVAL;
 	}
 
-	if (start + count >= max_count)
+	if (start + count > max_count)
 		return -EINVAL;
 
 	count = min_t(int, count, max_count);