zygo: config: build dm-log-writes, dm-flakey and dm-crypt in

zygo: config: build dm-log-writes, dm-flakey and dm-crypt in

The test kernels install a single bzImage with no module tree, so =m means
the dm target simply does not exist at runtime.  DM_LOG_WRITES=m blocked the
entire Stage 0 logged-write replay matrix, DM_FLAKEY=m parts of the octopus
suite, and DM_CRYPT=m the crypted soak arm.

DM_CRYPT depends on (TRUSTED_KEYS || TRUSTED_KEYS=n) and TRUSTED_KEYS=m
capped it at m, so TRUSTED_KEYS is turned off here.