drm/i915/guc: Add fetch of hwconfig blob

drm/i915/guc: Add fetch of hwconfig blob

Implement support for fetching the hardware description table from the
GuC. The call is made twice - once without a destination buffer to
query the size and then a second time to fill in the buffer.

The table is stored in the GT structure so that it can be fetched once
at driver load time. Keeping inside a GuC structure would mean it
would be release and reloaded on a GuC reset (part of a full GT
reset). However, the table does not change just because the GT has been
reset and the GuC reloaded. Also, dynamic memory allocations inside
the reset path are a problem.

Note that the table is only available on ADL-P and later platforms.

v2 (John's v2 patch):
 * Move to GT level to avoid memory allocation during reset path (and
   unnecessary re-read of the table on a reset).

v5 (of Jordan's posting):
 * Various changes made by Jordan and recommended by Michal
   - Makefile ordering
   - Adjust "struct intel_guc_hwconfig hwconfig" comment
   - Set Copyright year to 2022 in intel_guc_hwconfig.c/.h
   - Drop inline from hwconfig_to_guc()
   - Replace hwconfig param with guc in __guc_action_get_hwconfig()
   - Move zero size check into guc_hwconfig_discover_size()
   - Change comment to say zero size offset/size is needed to get size
   - Add has_guc_hwconfig to devinfo and drop has_table()
   - Change drm_err to notice in __uc_init_hw() and use %pe

v6 (of Jordan's posting):
 * Added a couple more small changes recommended by Michal
 * Merge in John's v2 patch, but note:
   - Using drm_notice as recommended by Michal
   - Reverted Michal's suggestion of using devinfo

v7 (of Jordan's posting):
 * Change back to drm_err as preferred by John

Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Acked-by: Jon Bloomfield <jon.bloomfield@intel.com>
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220306232157.1174335-2-jordan.l.justen@intel.com