Change existing build system for CFStream
diff --git a/src/core/lib/iomgr/ev_epollsig_linux.cc b/src/core/lib/iomgr/ev_epollsig_linux.cc
index 1e30f66..4991f46 100644
--- a/src/core/lib/iomgr/ev_epollsig_linux.cc
+++ b/src/core/lib/iomgr/ev_epollsig_linux.cc
@@ -1721,7 +1721,7 @@
}
#else /* defined(GRPC_LINUX_EPOLL_CREATE1) */
-#if defined(GRPC_POSIX_SOCKET)
+#if defined(GRPC_POSIX_SOCKET_EV_EPOLLSIG)
#include "src/core/lib/iomgr/ev_epollsig_linux.h"
/* If GRPC_LINUX_EPOLL_CREATE1 is not defined, it means
epoll_create1 is not available. Return NULL */