Beside regular feed control interrupt, the driver requires also hash
interrupt for older SoCs (samsung,s5pv210-secss). However after
requesting it, the interrupt handler isn't doing anything with it, not
even clearing the hash interrupt bit.

Driver does not provide hash functions so it is safe to remove the hash
interrupt related code and to not require the interrupt in Device Tree.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>