Reparent some branches from cvs2svn
Some branches from the cvs2svn period in the GCC history should be reparented, where cvs2svn messed up identifying a parent for the branch-creation commit.
See https://gcc.gnu.org/ml/gcc/2019-11/msg00000.html for a list of 39 such reparentings. I think each line "REPARENT: A B C D E F" is equivalent to a single reposurgeon command along the lines of "<F>|<B> reparent --use-order
" (not tested, and the use-order is only to reflect the intended logical semantics of the REPARENT lines, all the parents are already earlier commits than the ones they are to be made parents of).
Edited by Joseph Myers