bus_generic_print_child.9: Document bus_print_domain

[jhb]

Summary

While here, cross-reference BUS_PRINT_CHILD (and fix a stale reference
to DEVICE_PRINT_CHILD which doesn't exist) and expand the text
describing the role of the helper functions.

[ziaee]

share/man/man9/bus_generic_print_child.9

38

Sir, xrefs in document descriptions are broken in many implementations like apropos. We discovered in this https://github.com/freebsd/freebsd-src/pull/1371 , and then I asked if Ingo would be willing to accept it as a bug on the mandoc mailing-tech mailing list that month and the maintainer asked us to not do that and gave us some nice contributions for jail.conf(5). Thank you for your consideration.

[jhb]

share/man/man9/bus_generic_print_child.9

38

Yeah, I noticed this as well (mdoc(7) mentions this limitation), but in this case I was only fixing what is already there. I could just turn it into plain text instead?

[jhb]

@kib btw while documenting this, I do wonder if we shouldn't just merge bus_print_child_domain into bus_print_child_footer?

[kib]

In D48373#1104032, @jhb wrote:

@kib btw while documenting this, I do wonder if we shouldn't just merge bus_print_child_domain into bus_print_child_footer?

Why? On the principle that it is not used by anything else? But there are already approx. 10 callers of the function.

[jhb]

In D48373#1104076, @kib wrote:

In D48373#1104032, @jhb wrote:

@kib btw while documenting this, I do wonder if we shouldn't just merge bus_print_child_domain into bus_print_child_footer?

Why? On the principle that it is not used by anything else? But there are already approx. 10 callers of the function.

More that if we wanted it to be in all bus drivers, we wouldn't have had to change existing (or future) bus drivers if it is part of the default footer. Perhaps not worth changing at this point.