crypto: fips - Depend on ansi_cprng

What about something like this?  It defaults the CPRNG to m and makes FIPS
dependent on the CPRNG.  That way you get a module build by default, but you can
change it to y manually during config and still satisfy the dependency, and if
you select N it disables FIPS as well.  I rather like that better than making
FIPS a tristate.  I just tested it out here and it seems to work well.  Let me
know what you think
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/Kconfig

@@ -23,11 +23,13 @@ comment "Crypto core or helper"
 
 config CRYPTO_FIPS
 	bool "FIPS 200 compliance"
+	depends on CRYPTO_ANSI_CPRNG
 	help
 	  This options enables the fips boot option which is
 	  required if you want to system to operate in a FIPS 200
 	  certification.  You should say no unless you know what
-	  this is.
+	  this is. Note that CRYPTO_ANSI_CPRNG is requred if this
+	  option is selected
 
 config CRYPTO_ALGAPI
 	tristate
@@ -787,12 +789,14 @@ comment "Random Number Generation"
 
 config CRYPTO_ANSI_CPRNG
 	tristate "Pseudo Random Number Generation for Cryptographic modules"
+	default m
 	select CRYPTO_AES
 	select CRYPTO_RNG
 	help
 	  This option enables the generic pseudo random number generator
 	  for cryptographic modules.  Uses the Algorithm specified in
-	  ANSI X9.31 A.2.4
+	  ANSI X9.31 A.2.4. Not this option must be enabled if CRYPTO_FIPS 
+	  is selected
 
 source "drivers/crypto/Kconfig"