[lld] [lld][NCF] Add missing llvm-mc invocation to arm64ec-codemap.test. (PR #70956)

[Anton Korobeynikov via llvm-commits]

asl wrote:

> @asl your revert created a new branch in the upstream repo, was that intentional?

@cjacek Actually yes :) We relaxed the protection rules to allow reverts from GitHub UI. But for testing we needed one real merged PR, and here it was. I deleted the revert branch created by GitHub

https://github.com/llvm/llvm-project/pull/70956