[lld] [LLD][RISCV][Zicfilp] Generate unlabeled landing pad-style PLT (PR #145461)

[Jessica Clarke via llvm-commits]

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jrtc27 wrote:

Please make this consistent with the equivalent code below. And probably it can be unified too, the body is the same, it's just replacing the nop at the end with an lpad at the start and using t2 instead of t3.

https://github.com/llvm/llvm-project/pull/145461