[libc] `__stack_chk_fail` baremetal dependencies (#76412)

`__stack_chk_fail` uses `write_to_stderr` and `abort` but these
currently aren't included in baremetal targets resulting in a CMake
build error:

```
CMake Error at /llvm-project/libc/cmake/modules/LLVMLibCObjectRules.cmake:693 (target_link_libraries):
  Target "libc.src.stdlib.abort" of type UTILITY may not be linked into
  another target.  One may link only to INTERFACE, OBJECT, STATIC or SHARED
  libraries, or to executables with the ENABLE_EXPORTS property set.
Call Stack (most recent call first):
  /llvm-project/libc/cmake/modules/LLVMLibCObjectRules.cmake:811 (create_entrypoint_object)
  /llvm-project/libc/cmake/modules/LLVMLibCObjectRules.cmake:891 (expand_flags_for_entrypoint_object)
  /llvm-project/libc/src/compiler/generic/CMakeLists.txt:1 (add_entrypoint_object)

CMake Error at /llvm-project/libc/cmake/modules/LLVMLibCLibraryRules.cmake:5 (get_target_property):
  get_target_property() called with non-existent target
  "libc.src.__support.OSUtil.osutil".
Call Stack (most recent call first):
  /llvm-project/libc/cmake/modules/LLVMLibCLibraryRules.cmake:36 (collect_object_file_deps)
  /llvm-project/libc/cmake/modules/LLVMLibCLibraryRules.cmake:36 (collect_object_file_deps)
  /llvm-project/libc/cmake/modules/LLVMLibCLibraryRules.cmake:85 (collect_object_file_deps)
  /llvm-project/libc/lib/CMakeLists.txt:26 (add_entrypoint_library)
```

To address these errors, we need to include `abort` in the list of
baremetal entrypoints. We also need to provide `write_to_stderr`
baremetal implementation, but this is challenging since there is no
uniform way to print a message on these platforms (sometimes there may
not be any way to print a message). We instead defer to
`__libc_log_write` which can be provided by the underlying platform. We
use a similar approach for `quick_exit`, defering to
`__libc_quick_exit`.

0 files changed, 0 insertions, 0 deletions