unwind: use -fno-rtti -fno-exceptions -funwind-tables

RTTI and exceptions are not needed for the unwinder, the use of C++ there is for
very specific cases, and does not require dynamic_cast nor does it use
exceptions.  This avoids unnecessary references to type information being
emitted.

git-svn-id: https://llvm.org/svn/llvm-project/libcxxabi/trunk@228408 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed