Fix build, fix epollex detection
diff --git a/src/python/grpcio/grpc_core_dependencies.py b/src/python/grpcio/grpc_core_dependencies.py
index 0d0a5fb..b742043 100644
--- a/src/python/grpcio/grpc_core_dependencies.py
+++ b/src/python/grpcio/grpc_core_dependencies.py
@@ -103,6 +103,7 @@
   'src/core/lib/iomgr/endpoint_pair_windows.c',
   'src/core/lib/iomgr/error.c',
   'src/core/lib/iomgr/ev_epoll_linux.c',
+  'src/core/lib/iomgr/ev_epollex_linux.c',
   'src/core/lib/iomgr/ev_poll_posix.c',
   'src/core/lib/iomgr/ev_posix.c',
   'src/core/lib/iomgr/exec_ctx.c',