LLVM JIT: n64_ops.c: Do not set RS in the LUI opcode, which uses RT
LLVM JIT: Use WeakAnyLinkage instead of InternalLinkage

This allows functions to reuse names and uses less memory than is
required by InternalLinkage, which keeps track of old functions in
order to avoid name collisions.
LLVM JIT: Recompile 34 new opcodes into LLVM IR

The new opcodes are SLLV, SRLV, SRAV, DSLLV, DSRLV, DSRAV, ADD, ADDU,
SUB, SUBU, AND, OR, XOR, NOR, SLT, SLTU, DADD, DADDU, DSUB, DSUBU,
ADDI, ADDIU, SLTI, SLTIU, ANDI, ORI, XORI, LUI, DADDI, DADDIU, MFHI,
MFLO, MTHI, MTLO.