ppc64le: expected localentry:0 `pthread_condattr_destroy'

[Josh Stone]

Hi folks,

I mentioned this regression to fweimer, and he suggested I should bring
it up to libc-alpha and binutils.  I was just trying to rebuild rustc on
Fedora Rawhide, and ppc64le alone failed with this localentry error.
Florian suspected that a binutils update in particular now enabled use
of PPC64_OPT_LOCALENTRY.

I reproduced the regression from old to new binutils, and uploaded those
artifacts here if anyone else wants to inspect them:

https://jistone.fedorapeople.org/rust-1.19.0-stage1-ppc64le-binutils-2.28.tar.xz
https://jistone.fedorapeople.org/rust-1.19.0-stage1-ppc64le-binutils-2.29.tar.xz

rust-1.19.0-stage1-ppc64le-binutils-2.28:
# LD_LIBRARY_PATH=./lib ./bin/rustc -V
rustc 1.19.0

rust-1.19.0-stage1-ppc64le-binutils-2.29:
# LD_LIBRARY_PATH=./lib ./bin/rustc -V
./bin/rustc: error while loading shared libraries:
./lib/libstd-c3a1748e15265da7.so: expected localentry:0
`pthread_condattr_destroy'