Release linux 6.16-1 to Unstable

Update to upstream kernel 6.16. Next to that, these are the most
noteworthy other changes that are part of this release:
- d/p: Drop "ARM: mm: Export __sync_icache_dcache() for xen-privcmd"
  The problem this patch was meant to fix, has been fixed upstream in
  kernel 5.3-rc3 already ... 6 years ago.
- d/p: Drop "arm64/acpi: Add fixup for HPE m400 quirks"
  When the patch was added in 2018, the product was already EOL and
  there weren't that many to begin with (and ~25% in the hands of
  Linaro). When trying to upstream it, it was NACKed. For several
  reasons, one of them being that a simple kernel command line parameter
  was enough as a workaround.
- d/p: Add "rockchip/drm: vop2: make vp registers nonvolatile" v2
  This patch is needed as since kernel 6.14-rc1 the screen of the
  PineTab2 stays blank when booted up with CONFIG_DRM=m. Accidentally
  found a workaround for this issue: closing the lid and opening it.
  Recently this patch was accepted upstream in the drm-misc-fixes branch
  so hopefully will make its way to the 6.17 release (after all).

Signed-off-by: Diederik de Haas <didi.debian@cknow.org>