[llvm] [DA] Add option to enable specific dependence test only (PR #164245)

[Ryotaro Kasuga via llvm-commits]

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kasuga-fj wrote:

Separated the tests for each method. It seems impossible to create fully dedicated tests for all methods due to certain reasons (e.g., `testSIV` calls `gcdMIVtest`), but generally looks fine to me.

https://github.com/llvm/llvm-project/pull/164245