MdeModulePkg:Refine the UiApp

Use new created libraries(Boot Manager,Device Manager,Boot Maintenance
Manager) in UiApp.So remove and refine relative code in UiApp.And update
the Nt32Pkg.dsc and MdeModulePkg.dsc.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18924 6f19259b-4bc3-4df7-8a09-765794883524