[llvm] RenameIndependentSubregs: Add missing sub-range for new IMPLICIT_DEFs (PR #89050)

[Petar Avramovic via llvm-commits]

petar-avramovic wrote:

This is shortest I could get it to still expose the bug, live interval fix in RenameIndependentSubregs can be reproduced with fewer instructions but to see effects of that fix, it still needs a couple extra instructions for register allocator to assign registers in such a way to expose the bug due to missing segment for big implicit def in %bb.1.

https://github.com/llvm/llvm-project/pull/89050