Log Message:
binutils: add upstream fixes for CVE-2020-35448.

From upstream commit log:

PR26574, heap buffer overflow in _bfd_elf_slurp_secondary_reloc_section

A horribly fuzzed object with section headers inside the ELF header.
Disallow that, and crazy reloc sizes.

	PR 26574
	* elfcode.h (elf_object_p): Sanity check section header offset.
	* elf.c (_bfd_elf_slurp_secondary_reloc_section): Sanity check
	sh_entsize.