CryptoPkg/BaseCryptLib:Remove redundant init

CryptoPkg/BaseCryptLib:Remove redundant init

CertCtx is used to be defined as a struct and ZeroMem is called to
init this struct. But now CertCtx is defined as a point, so use
ZeroMem (&CertCtx, sizeof (CertCtx)) is not correct any more.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Xiaoyu Lu <xiaoyu1.lu@intel.com>
Cc: Guomin Jiang <guomin.jiang@intel.com>
Signed-off-by: Wenyi Xie <xiewenyi2@huawei.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>