modules: update OpenWrt

a02d9a7d9f tools: tplink-safeloader: add C7v5 EU SupportList
709d080da5 base-files: fix unkillable processes after restart
216c04ff20 kernel: bump 4.14 to 4.14.82
07ef8b70b8 kernel: bump 4.9 to 4.9.138

Compile-tested: ar71xx, ipq40xx, x86-64
Runtime-tested: ar71xx