drm/xe: Don't copy pinned kernel bos twice on suspend

drm/xe: Don't copy pinned kernel bos twice on suspend

We were copying the bo content the bos on the list
"xe->pinned.late.kernel_bo_present" twice on suspend.

Presumingly the intent is to copy the pinned external bos on
the first pass.

This is harmless since we (currently) should have no pinned
external bos needing copy since
a) exernal system bos don't have compressed content,
b) We do not (yet) allow pinning of VRAM bos.

Still, fix this up so that we copy pinned external bos on
the first pass. We're about to allow bos pinned in VRAM.

Fixes: c6a4d46ec1d7 ("drm/xe: evict user memory in PM notifier")
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: <stable@vger.kernel.org> # v6.16+
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://lore.kernel.org/r/20250918092207.54472-2-thomas.hellstrom@linux.intel.com