CryptoPkg/dsc: Enable MD5 when CRYPTO_SERVICES enable MD5

CryptoPkg/dsc: Enable MD5 when CRYPTO_SERVICES enable MD5

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3021

CRYPTO_SERVICES PACKAGES and ALL config would enable MD5
function. So explicitly enable MD5 while CRYPTO_SERVICES
are set PACKAGES and ALL.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Xiaoyu Lu <xiaoyux.lu@intel.com>
Cc: Guomin Jiang <guomin.jiang@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Zhichao Gao <zhichao.gao@intel.com>
Message-Id: <20201112055558.2348-4-zhichao.gao@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>