crypto: mediatek - remove obsolete driver

The crypto mediatek driver has been replaced by the inside-secure
driver now. Remove this driver to avoid having duplicate drivers.

Signed-off-by: Vic Wu <vic.wu@mediatek.com>
Acked-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>