Fix build for old OS X and MacAppStore.

Telegram/gyp/settings_mac.gypi

@@ -89,6 +89,7 @@
         ],
       },
       'defines': [
+        'OS_MAC_OLD',
         'RANGES_CXX_THREAD_LOCAL=0',
       ],
     }, {
@@ -103,5 +104,11 @@
         ],
       },
     }],
+    [ 'build_macstore', {
+      'defines': [
+        'TDESKTOP_DISABLE_AUTOUPDATE',
+        'OS_MAC_STORE',
+      ],
+    }]
   ],
 }

Telegram/gyp/telegram_mac.gypi

@@ -37,9 +37,6 @@
       },
     },
   }], [ 'build_macold', {
-    'defines': [
-      'OS_MAC_OLD',
-    ],
     'xcode_settings': {
       'OTHER_CPLUSPLUSFLAGS': [ '-nostdinc++' ],
       'OTHER_LDFLAGS': [