drm/i915: Move locking and unclaimed check into mmio_debug_{suspend, resume}

Moving the locking for MMIO debug (and the final check for unclaimed
accesses when resuming debug after a userspace-initiated forcewake) will
make it simpler to completely skip MMIO debug handling on uncores that
don't support it in future patches.

Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220906234934.3655440-2-matthew.d.roper@intel.com


Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>