drm/xe/devcoredump: Improve section headings and add tile info

The xe_guc_exec_queue_snapshot is not really a GuC internal thing and
is definitely not a GuC CT thing. So give it its own section heading.
The snapshot itself is really a capture of the submission backend's
internal state. Although all it currently prints out is the submission
contexts. So label it as 'Contexts'. If more general state is added
later then it could be change to 'Submission backend' or some such.

Further, everything from the GuC CT section onwards is GT specific but
there was no indication of which GT it was related to (and that is
impossible to work out from the other fields that are given). So add a
GT section heading. Also include the tile id of the GT, because again
significant information.

Lastly, drop a couple of unnecessary line feeds within sections.

v2: Add GT section heading, add tile id to device section.

Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Julia Filipchuk <julia.filipchuk@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241003004611.2323493-4-John.C.Harrison@Intel.com