Roll back to using malloc/realloc on some of spoolss in head.

Roll back to using malloc/realloc on some of spoolss in head.
I'm having problems with talloc_realloc in the 2.2 branch and I
want a stable reference.

The only problem is this breaks the clean auto-generated code
in *one* call in srv_spoolss.c (the rfnpcnex call).

Jeremy.