IMPORTANT (Sparc): Switch-over to new C front-end

Just like we did for X86:

We're now switching over to the new C frontend on solaris. If you are
doing development on solaris, you *must* make the following changes to
your setup:

1. Change your llvm-gcc symlink (or alias, or whatever you use) to point
   to ~lattner/local/sparc/llvm-gcc/bin/gcc
2. Add the following environment variable to your startup scripts:
   setenv LLVM_LIB_SEARCH_PATH /home/vadve/lattner/local/sparc/llvm-gcc/bytecode-libs