Made LOAD and STORE instructions to work.

Added ADDR and MEM definitions and created complex pattern matching
so that LOAD and STORE instructions would be selected.
Coded eliminateFrameIndex() based on MBlaze implementation
Added emitPrologue/emitEpilogue for TeeRISC based on MicroBlaze.

Need to revisit variable argument calling convention.
Added LowerFormalArugments()
Implemented LowerCall() based MBlaze.

Also renamed TeeRISC specific 'call' instruction to consistent with MBlaze
Also added MCTargetDesc/TeeRISCBaseInfo.h file which should have
committed with last change.