Do not build MySQL Router.
It is a set of tools and libraries used for the InnoDB cluster.

However without MySQL SHELL it can't be operated.
We don't pack the MySQL SHELL, so don´t build the router at all.

--- mysql-8.0.13/CMakeLists.txt    2018-10-07 10:44:22.000000000 +0200
+++ mysql-8.0.13/CMakeLists.txt_patched    2018-10-23 03:10:01.490792624 +0200
@@ -1046,7 +1046,7 @@ CONFIGURE_FILE(${CMAKE_SOURCE_DIR}/sql/s

 # depends on mysql_version.h to exist
 IF(NOT WITHOUT_SERVER)
-  ADD_SUBDIRECTORY(router)
+#  ADD_SUBDIRECTORY(router)
 ENDIF()

 GET_PROPERTY(CWD_DEFINITIONS DIRECTORY PROPERTY COMPILE_DEFINITIONS)