Fixes for --enable-system-abi.
Fixes for --enable-system-abi.

Fixed to work when REG_BASIC is already defined, also fixed to work
when one of REG_NOSPEC or REG_LITERAL is already defined.

darcs-hash:20060521071726-ced27-3ea68b2482d112fbebd3c2c14fc39cb8caffb1d9.gz

laurikari/tre,amlweems/tre,amlweems/tre,amlweems/tre,laurikari/tre,laurikari/tre