crypto: atmel-sha204a - Add support for ATSHA204 cryptochip

ATSHA204 is predecessor of ATSHA204A which supports less features and some
of them are slightly different.

Introduce a new compatible string for ATSHA204 cryptochip "atmel,atsha204".

Current version of Linux kernel driver atmel-sha204a.c implements only hw
random number generator which is same in both ATSHA204 and ATSHA204A
cryptochips. So driver already supports also ATSHA204 hw generator, so just
simply extends list of compatible strings.

Signed-off-by: Pali Rohár <pali@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>