crypto: atmel - remove set but not used variable 'alg_name'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/crypto/atmel-tdes.c: In function 'atmel_tdes_setkey':
drivers/crypto/atmel-tdes.c:803:14: warning: variable 'alg_name' set but not used [-Wunused-but-set-variable]

It is not used any more since
commit 52ea3cd2 ("crypto: atmel - Forbid 2-key 3DES in FIPS mode")

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>