crypto: user - Add CRYPTO_MSG_DELRNG

This patch adds a new crypto_user command that allows the admin to
delete the crypto system RNG.  Note that this can only be done if
the RNG is currently not in use.  The next time it is used a new
system RNG will be allocated.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

include/uapi/linux/cryptouser.h

@@ -25,6 +25,7 @@ enum {
 	CRYPTO_MSG_DELALG,
 	CRYPTO_MSG_UPDATEALG,
 	CRYPTO_MSG_GETALG,
+	CRYPTO_MSG_DELRNG,
 	__CRYPTO_MSG_MAX
 };
 #define CRYPTO_MSG_MAX (__CRYPTO_MSG_MAX - 1)