When CRC32 is disabled, zonefs cannot be linked:

ld: fs/zonefs/super.o: in function `zonefs_fill_super':

Add a Kconfig 'select' statement for it.

Fixes: 8dcc1a9d ("fs: New zonefs file system")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>