Use global value as key for regs
Use global value as key for regs

Define global value as key for regs dict.

Signed-off-by: Elta Era <cfad527e9c23d1602b87bc3510b792e118bb78c8@gmail.com>

elta/MipsInstructionEncodeAndDecode,elta/MipsInstructionEncodeAndDecode,elta/MipsInstructionEncodeAndDecode