haskell-llvm-general-pure: disable tests
haskell-llvm-general: disable tests
llvm-general: bring back version 3.3.5.*
idris: fix by using llvm-general 3.3.5.*

I tried jailbreaking, but this didn't work as llvm-general is an
optional (but enabled by default) dependency.

Manual patching revealed idris gets confused over the
llvm-general/llvm-general-pure split.