SecurityPkg: Remove code under UserIdentification folder.

SecurityPkg: Remove code under UserIdentification folder.

BZ:https://bugzilla.tianocore.org/show_bug.cgi?id=1427

1. UserIdentifyManagerDxe is used to provide UserManagerProtocol.
2. UserProfileManagerDxe provides UI setting
3. PwdCredentialProviderDxe & UsbCredentialProviderDxe are implementation
   examples.

Remove above features because of no platform use it.

Cc: Zhang Chao B <chao.b.zhang@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Chen A Chen <chen.a.chen@intel.com>
Reviewed-by: Zhang Chao B <chao.b.zhang@intel.com>