backporting some game fixes from upstream rsp repo

Currently, the libretro Mupen64Plus core isn't in sync with the modern changes to the cxd4 RSP component, and I have not really finished optimizing parts of the RSP myself.  Now that the angrylion RDP is working, some bugs have been spotted in _Resident Evil 2_.  I have recognized these to be RSP interpreter issues--regressions from a year or two ago back when I was still experimenting early on with SIMD vectorization of the interpreter functions.  As a temporary fix until there is time to fully port the upstream cxd4 rsp to libretro, these commits should fix a few games--_Harvest Moon 64_, _Resident Evil 2_, _Wrestlemania 2000_, and some other weird game from hearsay that I can't remember the name of.