Roll back code modify by commit 9e47e6f90880,
if ForceRebase not False or True, the GenFv command not need add parameter
Cc: Liming Gao <liming.gao@intel.com>
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Yunhua Feng <yunhuax.feng@intel.com>
599bb2be1f