MIPS64: Added MINx/MAXx, BOVC and BNVC instructions for MIPS64r6 in assembler.

TEST=
MIPS64: Fix DoModI for smi inputs.

TEST=mjsunit/smi-mul
MIPS64: Added CMP.D Mips64r6 instructions to the simulator.
MIPS64: Fix compare in BranchF to use fmt L.

TEST=
Merge branch 'mips64-gbl' of github.com:paul99/v8m-rb into mips64-gbl

Conflicts:
	src/mips64/assembler-mips64.cc
	src/mips64/assembler-mips64.h
MIPS64: First part of dissasembler test update for MIPS64r6 ISA.

TEST=test-disasm-mips64