[libunwind] convert error logs to _LIBUNWIND_LOG/_LIBUNWIND_LOG0.
Use the `_LIBUNWIND_LOG` and `_LIBUNWIND_LOG0` macros instead of
the explicit `fprintf` call.
This was previously done in r292721 as a cleanup and then reverted
in r293257 because the implementation in r292721 relied on a GNU
extension. This implementation avoids the use of an extension
by using a second macro instead, and allows to avoid the dependency
on fprintf if _LIBUNWIND_BARE_METAL is defined.
git-svn-id: https://llvm.org/svn/llvm-project/libunwind/trunk@321441 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed
