MIPS64: Add r6 arch. variant.
MIPS64: Disable Movz, Movn in generated code for R6.
MIPS64: Bypass removed jr instruction in r6.
MIPS64: Refactor and make multiply operations compliant in generated code for new rev.

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MIPS64: Refactor and make div/mod operations compliant to R6 rev.

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MIPS64: Make BranchF compliant to R6.

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MIPS64: Added support for necessary instructions for MIPS64r6 in assembler.

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Conflicts:

	src/mips64/assembler-mips64.cc
	src/mips64/assembler-mips64.h
MIPS64: Unbreak build, fix Mulh() macro.

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MIPS64: Refactor heap numbers compare in ICCompare stub for r6.

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Revert "MIPS: add data tracing to the 32-bit MIPS simulator."

This reverts commit d7535d7ae591c1c6c17702b9396a96641f8e1fc9.

Conflicts:

	src/mips/simulator-mips.cc
MIPS: Clean clobbered mips32 file.
MIPS64: Added MINx/MAXx, BOVC and BNVC instructions for MIPS64r6 in assembler.

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