Support for twin loads.

Support for twin loads.

src/arch/sparc/isa/decoder.isa:
    Changed the names of the twin loads to match the 2005 spec. They still use the old format though.
src/arch/sparc/isa/formats/mem/blockmem.isa:
    Added code to generate twin loads
src/arch/sparc/isa/formats/mem/util.isa:
    Added an alignment check for twin loads
src/arch/sparc/isa/operands.isa:
    Comment explaining twin load operands.

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extra : convert_revision : ad42821a97dcda17744875b1e5dc00a9642e59b7