refs: remove unused function invalidate_ref_cache

[git/git-svn.git] / LGPL-2.1

 While most of this project is under the GPL (see COPYING), the xdiff/
 library and some libc code from compat/ are licensed under the
 GNU LGPL, version 2.1 or (at your option) any later version and some
 other files are under other licenses.  Check the individual files to
 be sure.

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That's all there is to it!