drm/xe/guc: Use a two stage dump for GuC logs and add more info

drm/xe/guc: Use a two stage dump for GuC logs and add more info

Split the GuC log dump into a two stage snapshot and print mechanism.
This allows the log to be captured at the point of an error (which may
be in a restricted context) and then dump it out later (from a regular
context such as a worker function or a sysfs file handler).

Also add a bunch of other useful pieces of information that can help
(or are fundamentally required!) to decode and parse the log.

v2: Add kerneldoc and fix a couple of comment typos - review feedback
from Michal W.
v3: Move chunking code to this patch as it makes the deltas simpler.
Fix a bunch of kerneldoc issues.
v4: Move the CS frequency out of the coredump snapshot function into
the debugfs only code (as that info is already part of the main
devcoredump). Add a header to the debugfs log to match the one in the
devcoredump to aid processing by a unified tool. Add forcewake to the
GuC timestamp read so it actually works.
v6: Add colon to GuC version string (review feedback by Julia F).

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/20241003004611.2323493-7-John.C.Harrison@Intel.com