m68k: defconfig: Update defconfigs for v5.16-rc1

  - Drop CONFIG_MCTP=m (can no longer be modular since commit
    78476d31 ("mctp: Add flow extension to skb")),
  - Drop CONFIG_BLK_DEV_CRYPTOLOOP=m (removed in commit 47e96246
    ("block: remove support for cryptoloop and the xor transfer")).

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20211115104956.2084032-1-geert@linux-m68k.org