[][openwrt][mt7988][tops][Fix L2TP/IPSec deadlock and check if TOPS HW exists]

[Description]
Fix HW issue between tunnel offload engine and crypto offload engine.

Check if TOPS HW exists before bring-up.

Sync from internal dev repo.
Commit-Id <5951d48c0b4fd965d66afddcb322f5244614076f>

[Release-log]
N/A

Change-Id: I132d67e23117f7bd14def1f8d42173eb0b7211f7
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/8023635
4 files changed