Use DT_PLTRELSZ if present

Author: rhelmot

cle/backends/elf/elf.py

@@ -987,6 +987,8 @@ def __register_dyn(self, seg_readelf):
             rela_tag = "DT_" + self.rela_type
             relsz_tag = rela_tag + "SZ"
             if rela_tag in self._dynamic:
+                if "DT_PLTRELSZ" in self._dynamic:
+                    relsz_tag = "DT_PLTRELSZ"
                 reloffset = AT.from_lva(self._dynamic[rela_tag], self).to_rva()
                 if relsz_tag not in self._dynamic:
                     raise CLEInvalidBinaryError(f"Dynamic section contains {rela_tag} but not {relsz_tag}")