drm/i915/guc: Reset implementation for new GuC interface

drm/i915/guc: Reset implementation for new GuC interface

Reset implementation for new GuC interface. This is the legacy reset
implementation which is called when the i915 owns the engine hang check.
Future patches will offload the engine hang check to GuC but we will
continue to maintain this legacy path as a fallback and this code path
is also required if the GuC dies.

With the new GuC interface it is not possible to reset individual
engines - it is only possible to reset the GPU entirely. This patch
forces an entire chip reset if any engine hangs.

v2:
 (Michal)
  - Check for -EPIPE rather than -EIO (CT deadlock/corrupt check)
v3:
 (John H)
  - Split into a series of smaller patches
v4:
 (John H)
  - Fix typo
  - Add braces around if statements in reset code
v5:
 (Checkpatch)
  - Fix warnings

Cc: John Harrison <john.c.harrison@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: John Harrison <john.c.harrison@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-9-matthew.brost@intel.com