jemalloc: Remove obsolete files from the exclusion list

These files are not present upstream, nor in the tree after
autoconf/configure.

Remove the FREEBSD-* from the exclusion list. This likely breaks
FREEBSD-upgrade, but that needs to be rewritten for being used with a
vendor branch (or just scaled back to be just a how-to, no the full
script). Remove the dot files, since the upgrade process doesn't create
them.

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