[llvm] [LTO] Sort DefinedGlobals in LTO cache key (PR #210025)

[Zhaoxuan Jiang via llvm-commits]

https://github.com/nocchijiang approved this pull request.

Could we add a regression test for this? Otherwise LGTM. The failed Linux check looks unrelated.

https://github.com/llvm/llvm-project/pull/210025