Unfortunately, just because the header is there doesn't mean anything will
actually work :(. Also, the check is based on the host vendor/os for now.
Yes, it's rather lame but it will do for now.
With this, QF will build on an almost fresh ps3toolchain install. Only two
"fixes" are needed:
o In $PS3DEV/ppu/powerpc64-ps3-elf: ln -s ../include sys-include
o libsamplerate cross-built and installed.