FPHSA: replace left-over VERSION by _FOUND_VERSION.

This was accidentally left out of commit aec27c152e (FPHSA: use more
localized _FOUND_VERSION instead of VERSION, 2017-09-05).

Fixes: #17281

Modules/FindPackageHandleStandardArgs.cmake

@@ -322,7 +322,7 @@ function(FIND_PACKAGE_HANDLE_STANDARD_ARGS _NAME _FIRST_ARG)
           endif ()
           unset(_VERSION_HEAD)
         else ()
-          if (NOT ${_NAME}_FIND_VERSION VERSION_EQUAL VERSION)
+          if (NOT ${_NAME}_FIND_VERSION VERSION_EQUAL _FOUND_VERSION)
             set(VERSION_MSG "Found unsuitable version \"${_FOUND_VERSION}\", but required is exact version \"${${_NAME}_FIND_VERSION}\"")
             set(VERSION_OK FALSE)
           else ()