crypto: atmel-sha204a - Fix OOM ->tfm_count leak
If memory allocation fails, decrement ->tfm_count to avoid blocking
future reads.
Cc: stable@vger.kernel.org
Fixes: da001fb651b0 ("crypto: atmel-i2c - add support for SHA204A random number generator")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>