m68k: defconfig: Update defconfigs for v5.17-rc3

  - Drop CONFIG_NFT_COUNTER=m (removed in commit 023223df
    ("netfilter: nf_tables: make counter support built-in")),
  - Drop CONFIG_NF_FLOW_TABLE_IPV4=m and CONFIG_NF_FLOW_TABLE_IPV6=m
    (can no longer be enabled since commit c42ba429 ("netfilter:
    flowtable: remove ipv4/ipv6 modules")),
  - Enable the new option for legacy fbcon hardware acceleration code on
    all platforms that have a frame buffer device that can make use of
    it,
  - Drop CONFIG_TEST_HASH=m (replaced by auto-modular
    CONFIG_HASH_KUNIT_TEST in commit 0acc968f ("test_hash.c:
    refactor into kunit")),
  - Enable modular build of the new siphash selftest.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20220123125543.2658445-1-geert@linux-m68k.org
Link: https://lore.kernel.org/r/20220207131008.2202977-1-geert@linux-m68k.org