Remove want_vtbl_{glob,symtab}, which aren't used and don't do anything useful.

Remove want_vtbl_{glob,symtab}, which aren't used and don't do anything useful.

Nothing visible on CPAN uses either. Passing either to Perl_get_vtbl() will
currently return NULL (as a runtime error, rather than a compile time error).

The case for want_vtbl_glob was removed from the switch in Perl_get_vtbl() in
c0c446747ad6c5bd (which eliminated the need for magic on typeglobs).
want_vtbl_symtab was added to the enum in perl.h with 8d2f45362e368d7d, but
no code was added to Perl_get_vtbl() as there is no corresponding vtable.