tools/dombuilder: Switch to using gfn terminology for console and xenstore rings

tools/dombuilder: Switch to using gfn terminology for console and xenstore rings

The sole use of xc_dom_translated() and xc_dom_p2m() outside of the domain
builder is for libxl_dom() to translate the console and xenstore pfns back
into useful values.  PV guest pfns are only interesting to the domain builder,
and gfns are the address space used by all other hypercalls.

Renaming the fields in xc_dom_image is deliberate, as it will cause
out-of-tree users of the dombuilder to notice the different semantics.

Correct the terminology throughout xc_dom_gnttab{_hvm,}_seed(), which are all
using gfns despite the existing variable names.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Release-acked-by: Julien Grall <julien.grall@linaro.org>
[ wei: fix stubdom build ]
Signed-off-by: Wei Liu <wei.liu2@citrix.com>