objcopy --extract-symbol

Calling bfd_copy_private_bfd_data is necessary to copy ELF file header
info.

binutils/
	* objcopy.c (copy_object): Don't omit bfd_copy_private_bfd_data
	call when extract_symbol.
bfd/
	* elf32-v850.c (v850_elf_copy_private_bfd_data): Remove assertion
	that input and output .note.renesas sections are same size.
	Instead, only copy input to output if they are.