Revert r282483 - [cmake] Add linker option "-Wl,-z,defs" in standalone build
Revert r282483 - [cmake] Add linker option "-Wl,-z,defs" in standalone build

Revert r282483 as it causes build failures due to missing symbols when
not linking to -lgcc_s (i.e. doing pure LLVM stack build). The patch can
be reintroduced when the build system is fixed to add all needed
libraries (libunwind, compiler-rt).

git-svn-id: 756ef344af921d95d562d9e9f9389127a89a6314@282524 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/libcxx,llvm-mirror/libcxx,llvm-mirror/libcxx,llvm-mirror/libcxx,llvm-mirror/libcxx