Follow-up to r1921029:

CMake: Separate STRINGS property values with ';'.

git-svn-id: https://svn.apache.org/repos/asf/apr/apr/trunk@1921046 13f79535-47bb-0310-9956-ffa450edef68

CMakeLists.txt

@@ -47,7 +47,7 @@ endif()
 set(apr_libname libapr-2)
 
 set(APR_XML_BACKEND "xmllite" CACHE STRING "XML library to use (expat|libxml|xmllite)")
-set_property(CACHE APR_XML_BACKEND PROPERTY STRINGS expat libxml2 xmllite)
+set_property(CACHE APR_XML_BACKEND PROPERTY STRINGS "expat;libxml2;xmllite")
 
 option(APR_INSTALL_PRIVATE_H  "Install selected private .h files (for httpd)"  OFF)
 option(APU_HAVE_SQLITE3     "Build SQLite3 DBD driver"     OFF)