Out of memory message should not allocate memory.

Out of memory message should not allocate memory.

This fixes [perl #40595].  When Perl_malloc reports an out of
memory error, it should not make calls to PerlIO functions that
may turn around and allocate memory using Perl_malloc.  A simple
write() should be ok, though.  Inspired by S_write_no_mem() from
util.c.  Also replaces the local write2 function, which did the
same thing slightly differently.

Under -DDEBUGGING, there are other calls to PerlIO_printf that are
also likely unsafe, but that problem is not addressed here.