- Clean up interface to Sparc register handling a bit:

   - Eliminate Sparc*Order classes, moving contents to Sparc*Class classes
   - get register name methods now return const char * const pointers instead
     of std::string's.
   - Added file header comments to SparcRegClassInfo.(cpp|h)
   - Moved BIG constant arrays out of SparcRegClassInfo.h, into
     SparcRegInfo.cpp.  This should allow a LOT of std::string constructors to
     not have to be called.

llvm-svn: 3295