cryptsetup kernel backend requires CONFIG_NET

[osresearch]

The cryptsetup checked in as part of fixing #46 has some problems. Among other config changes, cryptsetup requires CONFIG_NET=y, as well as as userspace options to be selected:

+CONFIG_CRYPTO_USER_API=y
+CONFIG_CRYPTO_USER_API_HASH=y
+CONFIG_CRYPTO_USER_API_SKCIPHER=y
+CONFIG_CRYPTO_USER_API_RNG=y
+CONFIG_CRYPTO_USER_API_AEAD=y

[osresearch]

Fixed in post 33c3 cleanup.