libstdc++: Fix std::any pretty printer [PR 68735]
This fixes errors seen on powerpc64 (big endian only) due to the
printers for std::any and std::experimental::any being unable to find
the manager function.
libstdc++-v3/ChangeLog:
PR libstdc++/65480
PR libstdc++/68735
* python/libstdcxx/v6/printers.py (function_pointer_to_name):
New helper function to get the name of a function from its
address.
(StdExpAnyPrinter.__init__): Use it.
(cherry picked from commit
dc2b372ed1b1e9af6db45051cff95478c7616807)