parted: make a warning message more informative

parted: make a warning message more informative

The following parted message is not very useful:

  Error: You requested a partition from 2.00MiB to 3.00MiB.
  The closest location we can manage is 2.00MiB to 3.00MiB.

Improve the message by including exact geometry (in sectors):

  ...requested a partition from 2.00MiB to 3.00MiB (sectors 2048..3072).
  ... location we can manage is 2.00MiB to 3.00MiB (sectors 2049..3072).

* parted/parted.c (do_mkpart): Include exact partition geometry in
the warning message.
* tests/t-lib-helpers.sh (normalize_part_diag_): Adapt to
handle the new form of the diagnostic.
* tests/t7000-scripting.sh: Adapt and change the name
of a temporary file.