FindJNI: Add arch-specific library dir for JDK 9 layout (#15408)

JDK9's directory structure changes and no jdk/jre exists.  The arch
lib path is now jdk/lib/<arch> (instead of jdk/jre/lib/<arch>).

Modules/FindJNI.cmake

@@ -114,6 +114,7 @@ if(_JAVA_HOME)
   JAVA_APPEND_LIBRARY_DIRECTORIES(JAVA_AWT_LIBRARY_DIRECTORIES
     ${_JAVA_HOME}/jre/lib/{libarch}
     ${_JAVA_HOME}/jre/lib
+    ${_JAVA_HOME}/lib/{libarch}
     ${_JAVA_HOME}/lib
     ${_JAVA_HOME}
     )