Add seti/clri instr
Enable SPFP/DPFP for EM; add -mav2em switch for EM proc
ArcV2 ready assembler

Conflicts:

	opcodes/arc-opc.c
Merge pull request #4 from foss-for-synopsys-dwc-arc-processors/claudiu-gas-2_23_2-ModsforVineetAndEnableSPFP_DPFPforEM

Add SETI/CLRI instructions; add -mav2em option for EM; Enable SPFP/DPFP for EM.