[libunwind] Flip order of extern "C" and attribute(visibility)

GCC doesn't seems to like having the attribute before extern, but
Clang accepts it either way. This patch makes it compile on both.

git-svn-id: https://llvm.org/svn/llvm-project/libunwind/trunk@243147 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed
tree: 6dab46b774d6e426bfc513f1e10c2a074a7d7dc7
  1. cmake/
  2. include/
  3. src/
  4. test/
  5. .arcconfig
  6. .clang-format
  7. CMakeLists.txt