PR libstdc++/59392: Fix ARM EABI uncaught throw from unexpected exception handler

PR libstdc++/59392: Fix ARM EABI uncaught throw from unexpected exception handler

libstdc++-v3/
	PR libstdc++/59392
	* libsupc++/eh_call.cc (__cxa_call_unexpected): Call __do_catch with
	the address of a null pointer, not with a null pointer to pointer.
	Copy comment for this case from eh_personality.cc:__cxa_call_unexpected.
	* testsuite/18_support/bad_exception/59392.cc: New file.

Co-Authored-By: Mark Seaborn <mseaborn@google.com>
From-SVN: r208519