BaseTools PeCoffLib: Fix the issue to get RelocationsStripped from TE image

BaseTools PeCoffLib: Fix the issue to get RelocationsStripped from TE image

If PE image has no relocation section, and has not set RELOCS_STRIPPED,
after it is converted to TE image, GenFw will set its relocation section
VirtualAddress to non-zero address, and keep Size value as Zero. MdePkg
BasePeCoffLib applied this rule to get RelocationsStripped attribute. But,
it is missing in BaseTools BasePeCoffLib.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Yonghong Zhu <yonghong.zhu@intel.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>