Updates MdePkg package version from 1.03 to 1.04

Signed-off-by: Gao, Liming <liming.gao@intel.com>
Reviewed-by: Tian, Hot <hot.tian@intel.com>

git-svn-id: svn://svn.code.sf.net/p/edk2/code/trunk/edk2/MdePkg@15065 6f19259b-4bc3-4df7-8a09-765794883524