Update amap_flutter_map.podspec

ios/amap_flutter_map.podspec

@@ -16,6 +16,7 @@ A new Flutter plugin.
   s.source_files = 'Classes/**/*'
   s.public_header_files = 'Classes/**/*.h'
   s.dependency 'Flutter'
+  s.dependency 'AMap3DMap'
   s.dependency 'AMapSearch'
   s.static_framework = true
   s.platform = :ios, '8.0'