This doesn't look like it's meant to build CellOS Lv-2 executables. Lv-2 uses a different ABI (binary format elf64-powerpc-celloslv2) than the standard PPC64 ABI. I don't see any patches addressing that in the git repo.
If there are any capable toolchain hackers out there wanting to create an open Lv-2 toolchain, take a look at the ABI changes documented in PS3_SDKDoc_e.chm (which was leaked a few days ago) in section "OS Low-level Specifications".
You can compare it to this to find the differences from the standard PPC64 ABI (binary format elf64-powerpc) that the upstream toolchain implements: http://refspecs.linuxfoundation.org/ELF/ppc64/
Once we got the toolchain we can worry about the rest (like Lv-2 using the Dinkumware libc / libstdc++ which isn't available for free)