MIPS64: rename files to include 'mips64', to match other arch.
Merge the iniital mips64 commit to the renamed base files.

Merge commit 'd658872c13f05297d4ca5a39b84f3c91bc691ea4' into rename
MIPS64: Fix up include paths and build files after rename to -mips64.

Note that some erroneus include paths were found, where some files
were including files from 'mips' (non64) directory.
Updating branch to current code.

Merge commit '41052a23c850791a414c08e224db4ab04764a73a' into rename-02
MIPS64: deop frame.

(cherry picked from commit 60fce74a382054d4cb32b69d36f5f7dc3cc1bc9e)

Conflicts:
	src/mips64/macro-assembler-mips64.cc (fixed)
MIPS64: missing daddu and daddiu.

(cherry picked from commit fe15fda7b993ef9f7d9d7e92a90caa7e3899fc1d)
MIPS64: fix smi handle in builtins-mips.cc.

(cherry picked from commit 097457bd4cb4e7cc00262d5cd5a98bf623e739fa)
MIPS64: fix smi handle in code-stubs-mips.cc.

(cherry picked from commit 2edb914c2b4f3821fc0b142a2f1f3b4c4542509e)