Cannot create LuaJIT environment with LuaRocks 3.0.0

[aperezdc]

Steps to reproduce

1. Create a LuaJIT profile as described in the README.
2. Set ROCKZ_LUAROCKS_VERSION=3.0.0 in the environment to use LuaRocks 3.
3. Create a new rockenv: rockz new testenv -p luajit.

Expected outcome

An usable rockenv with LuaRocks 3.0.0 is created which uses LuaJIT.

Actual outcome

LuaRocks' fails installing at the make bootstrap step with the following output:

Initializing project luarocks-3.0.0 ...
Adding entries to .gitignore ...
Preparing ./.luarocks/ ...
Preparing ./lua_modules/ ...
Preparing ./lua ...

No existing manifest. Attempting to rebuild...
luarocks 3.0.0-1 is now installed in /home/aperez/.rockenvs/testenv (license: MIT)

/home/aperez/.rockenvs/testenv/bin/lua: ...env/lib/luarocks/rocks-5.1/luarocks/3.0.0-1/bin/luarocks:6: loop or previous error loading module 'luarocks.loader'
stack traceback:
        [C]: in function 'require'
        ...env/lib/luarocks/rocks-5.1/luarocks/3.0.0-1/bin/luarocks:6: in main chunk
        [C]: at 0x00404680