[llvm] recalculate the live interval of the defined register of xvmaddmdp in the VSX FMA mutation pass. (PR #116071)

[Kazu Hirata via llvm-commits]

kazutakahirata wrote:

I've fixed a warning from this PR with: https://github.com/llvm/llvm-project/commit/806a936b36553f284c2c68e67fd60abc75b200e6

https://github.com/llvm/llvm-project/pull/116071