[libunwind] [Mips] Fixed libunwind::Registers_mips_o32::jumpto to allow for load delay (PR #152942)

[Alex Rønne Petersen via cfe-commits]

alexrp wrote:

> Note: I'm unsure if this is necessary on mips64, I've added it for good measure though

It doesn't really matter at the end of the day, but just FYI, load delay slots were removed in MIPS II, and the first 64-bit version of the architecture was MIPS III.

https://github.com/llvm/llvm-project/pull/152942