Automatically allocate hba indexes if not given
Automatically allocate hba indexes if not given

Move next_hba_index from targetcli and simplify

use helper function to iterate hbas. Use for All() and _next_hba_index().

Change param order for Backstore and all descendants, since index has a
default value now.

Signed-off-by: Andy Grover <b7d524d2f5cc5aebadb6b92b08d3ab26911cde33@redhat.com>

mikenawrocki/rtslib-fb,cvubrugier/rtslib-fb,agrover/rtslib-fb,mikenawrocki/rtslib-fb