configs: enable CONFIG_CRYPTO_LZ4HC=m and support bcachefs-tools dkms build

[leezu]

Enable CONFIG_CRYPTO_LZ4HC=m LZ4 High Compression mode, a dependency of bcachefs-tools dkms module.

CC [M]  src/fs/bcachefs/vfs/direct.o
  CC [M]  src/fs/bcachefs/vfs/pagecache.o
  CC [M]  src/fs/bcachefs/debug/async_objs.o
  CC [M]  src/fs/bcachefs/module-version.o
  LD [M]  src/fs/bcachefs/bcachefs.o
  MODPOST Module.symvers
ERROR: modpost: "LZ4_compress_HC" [src/fs/bcachefs/bcachefs.ko] undefined!
make[3]: *** [/usr/src/linux-headers-6.18.4-v8+/scripts/Makefile.modpost:147: Module.symvers] Error 1
make[2]: *** [/usr/src/linux-headers-6.18.4-v8+/Makefile:1960: modpost] Error 2
make[1]: *** [/usr/src/linux-headers-6.18.4-v8+/Makefile:248: __sub-make] Error 2
make[1]: Leaving directory '/var/lib/dkms/bcachefs/v1.35.2-8-g674e2979007c/build'
make: *** [Makefile:248: __sub-make] Error 2
make: Leaving directory '/usr/src/linux-headers-6.18.4-v8+'