Typo in macOS Sierra macro in configure
sbs reports that there is a typo in the MAC_OS_VERSION_10_12 macro in: https://gitweb.torproject.org/tor.git/tree/configure.ac#n433 (It's missing an 'X_'.)
This has no impact, because we define MAC_OS_VERSION_10_12 if it's not defined (which it never is).
This was introduced in commit 16fcbd21 in tor-0.2.8.10.
Reported by Simone Basso, please credit in changes file.