MdeModulePkg: Retrieve boot manager menu from any fv

MdeModulePkg: Retrieve boot manager menu from any fv

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3384

Currently, UefiBootManagerLib has the below assumption:
  Assume the BootManagerMenuFile is in the same FV as the module links to this library.
It has some limitation now, so remove the assumption.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Zhichao Gao <zhichao.gao@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Reviewed-by: Hao A Wu <hao.a.wu@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Signed-off-by: Zhiguang Liu <zhiguang.liu@intel.com>