[libc++abi] Do not declare __cxa_finalize and __cxa_atexit in <cxxabi.h>

These functions are not defined by libc++abi, so they don't belong in <cxxabi.h>.

Differential Revision: https://reviews.llvm.org/D75795

GitOrigin-RevId: 8bd0dc5bfe23fdfba110eefd33ff658289a307ab
1 file changed