r9739: conver the reg_objects (REGSUBKEY_CTR & REGVAL_CTR) to use

r9739: conver the reg_objects (REGSUBKEY_CTR & REGVAL_CTR) to use
the new talloc() features:

 Note that the REGSUB_CTR and REGVAL_CTR objects *must* be talloc()'d
 since the methods use the object pointer as the talloc context for
 internal private data.

 There is no longer a regXXX_ctr_intit() and regXXX_ctr_destroy()
 pair of functions.  Simply TALLOC_ZERO_P() and TALLOC_FREE() the
 object.

Also had to convert the printer_info_2->NT_PRINTER_DATA field
to be talloc()'d as well.  This is just a stop on the road to
cleaning up the printer memory management.
(This used to be commit ef721333ab9639cb5346067497e99fbd0d4425dd)