more fp fixes

more fp fixes
fix unaligned accesses in mmaped disk device

src/arch/sparc/isa/decoder.isa:
    get (ld|st)fsr ops working right. In reality the fp enable check needs to go higher up in the emitted code
src/arch/sparc/isa/formats/basic.isa:
    move the cexec into the aexec field
src/cpu/exetrace.cc:
    copy the exception state from legion when we get it wrong. We aren't going to get it right without an fp emulation layer
src/dev/sparc/mm_disk.cc:
src/dev/sparc/mm_disk.hh:
    fix unaligned accesses in the memory mapped disk device

--HG--
extra : convert_revision : aaa33096b08cf0563fe291d984a87493a117e528