Remove cache var Trilinos_ENABLE_EXPORT_MAKEFILES (trilinos#8498, Tri…

…BITSPub/TriBITS#299)

Support for Makefile.export.* files was removed from TriBITS and snaphsotted
into Trilinos a long time ago.  This support was removed in the Trilinos 14.0
release.  There is no reason to keep this cache variable anymore.  It just
clutters up the base CMakeLists.txt file.

CMakeLists.txt

@@ -105,11 +105,6 @@ ENDIF ()
 
 message(STATUS "The Current CXX Standard is : " ${CMAKE_CXX_STANDARD})
 
-# Force off support for Makefile.export.* files while TriBITS is refactored to
-# remove this (#8498)
-SET(${PROJECT_NAME}_ENABLE_EXPORT_MAKEFILES OFF CACHE BOOL
-  "Support being removed from TriBITS (see trilinos/Trilinos#8498)" FORCE)
-
 # Define empty macro to allow Kokkos and KokkosKernels to keep working until
 # updated versions after Kokkos 4.1 are snapshotted in.
 macro(tribits_exclude_autotools_files)