MdeModulePkg UefiBootManagerLib: Ignore BootManagerMenu from LoadFile
    
    BootManagerMenu boot option is handled by EfiBootManagerGetBootManagerMenu.
    Don't need to handle it again when parse LoadFile protocol.
    
    In V2, use "BootManagerMenu" instead of "BootMenuApp".
    
    Contributed-under: TianoCore Contribution Agreement 1.0
    Signed-off-by: Liming Gao <liming.gao@intel.com>
    Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
    Reviewed-by: Sunny Wang <sunnywang@hpe.com>