crypto: atmel-sha204a - Set hwrng quality to lowest possible

According to the review by Bill Cox [1], the Atmel SHA204A random number
generator produces random numbers with very low entropy.

Set the lowest possible entropy for this chip just to be safe.

[1] https://www.metzdowd.com/pipermail/cryptography/2014-December/023858.html



Fixes: da001fb6 ("crypto: atmel-i2c - add support for SHA204A random number generator")
Cc: <stable@vger.kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>