a4eadb1256
Extend OptionalObsoleteFiles.inc to delete all lib32 files when MK_LIB32 is set to no on a system that previously had lib32 libraries installed. Also, to prevent "make delete-old-dirs" from always deleting lib32 directories after an installworld, move the lib32 subtree to its own mtree file that only gets applied when MK_LIB32=yes. Test: Ran "make delete-old" and "make delete-old-libs" on a system that never had MK_LIB32 enabled, and on a system where MK_LIB32 was enabled and later disabled. Did this both on amd64 and powerpc64. Test: Ran "make tinderbox" without errors. Reviewed by: emaste Differential Revision: https://reviews.freebsd.org/D3923