scons: Use MacPorts' location for man pages

Upstream-Status: Inappropriate [configuration]
Signed-off-by: Lawrence Velázquez <larryv@macports.org>
--- setup.py.orig	2019-01-07 21:00:38.000000000 -0600
+++ setup.py	2019-01-08 08:21:23.000000000 -0600
@@ -380,7 +380,7 @@
             if is_win32:
                 dir = 'Doc'
             else:
-                dir = os.path.join('man', 'man1')
+                dir = os.path.join('share', 'man', 'man1')
             self.data_files = [(dir, man_pages)]
             man_dir = os.path.join(self.install_dir, dir)
             msg = "Installed SCons man pages into %s" % man_dir