drm/i915/guc: More debug print updates - GuC reg capture

Update a bunch more debug prints to use the new GT based scheme.

v2: Upgrade the no node found message to a warning on the grounds of
it being quite important if the error capture can't find any register
state information.

Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230207050717.1833718-4-John.C.Harrison@Intel.com