Added include dirs

Author: pkittenis

setup.py

@@ -61,7 +61,10 @@
 
 runtime_library_dirs = ["$ORIGIN/."] if not SYSTEM_LIBSSH2 else None
 _lib_dir = os.path.abspath("./build_dir/src") if not SYSTEM_LIBSSH2 else "/usr/local/lib"
-include_dirs = ["libssh2/include"] if ON_WINDOWS or not SYSTEM_LIBSSH2 else ["/usr/local/include"]
+include_dirs = ["libssh2/include"] if ON_WINDOWS or not SYSTEM_LIBSSH2 else [
+    "/usr/local/include",
+    "/opt/local/include",
+]
 
 extensions = [
     Extension(sources[i].split('.')[0].replace(os.path.sep, '.'),