MdeModulePkg UefiBootManagerLib: Rename BootMenuApp to BootManagerMenu
MdeModulePkg UefiBootManagerLib: Rename BootMenuApp to BootManagerMenu

Rename local function name BootMenuApp to BootManagerMenu to align to
other public function name.

In V2, use "BootManagerMenu" instead of "BootMenuApp".

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Liming Gao <6480311aeeb4b006862f6d13ebabddc03f51e507@intel.com>
Reviewed-by: Ruiyu Ni <9fa3a6894a36bca79e6a72ad65af5a5702efecd1@intel.com>
Reviewed-by: Sunny Wang <74be04b34988dab727259a50c8e026e88682f7c8@hpe.com>

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